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A TEXT-BOOK 

OF 

OPERATIVE DENTISTRY 



LIST OF CONTRIBUTORS. 

J. P. BUCKLEY, PH. G., D. D. S., 

Professor of Materia Medica and Therapeutics, Chicago College 
of Dental Surgery. 

W. A. CAPON, D. D. S., 

Lecturer and Instructor of Dental Ceramics, Dental Department, 
University of Pennsylvania. 

GEORGE W. COOK, D. D. S., 

Dean of the College of Dentistry, University of Illinois, Chicago. 

FERDINAND J. S. GORGAS, A. M., M. D., D. D. S., 

Dean and Professor of Principles of Dental Science, Oral Surgery 
and Dental Prosthesis in the University of Maryland, Dental 
Department; Author of "Dental Medicine." 

ELLISON HILLYER, D. D. S.. 

Professor of Prosthetic Dentistry and Orthodontia, New York 
College of Dentistry. 

GEORGE EDWIN HUNT, M. D., D. D. S., 

Dean of the Indiana Dental College, Indianapolis. 

C. N. JOHNSON, M. A., L. D. S., D. D. S., 

Professor of Operative Dentistry in the Chicago College of 
Dental Surgery; Editor of "The Dental Review." 

C. EDMUND KELLS, JR., D. D. S., 

New Orleans. 

GARRETT NEWKIRK, M. D., 

Member of the California State Board of Dental Examiners, 
Former Dean and Professor of Operative Dentistry, College of 
Dentistry, University of Southern California. 

JOHN EGBERT NYMAN, D. D.S., 

Chicago. * ' 

ALFRED OWRE, D. M. D., M. D., C. M., 

Dean and Professor of Operative Dentistry and Metallurgy, 
College of Dentistry, University of Minnesota. 

JOHN DEANS PATTERSON, D. D. S., 

Professor of Dental Pathology, Kansas City Dental College. 

HERMANN PRINZ, M. D., D. D. S., 

Professor of Materia Medica, Therapeutics and Pathology, 
Dental Department Washington University, St. Louis. 

HERBERT A. PULLEN, D. M. D., 

President of the American Society of Orthodontists, 1906-07 ; 
Instructor in the Angle School of Orthodontia, Session of 1900; 
Member of the New York State Dental Society, Buffalo Dental 
Association, National Dental Association, etc. 

CHARLES R. TURNER, D. D. S., M. D., 

Professor of Mechanical Dentistry and Metallurgy, Department 
of Dentistry, University of Pennsylvania. 

A. E. WEBSTER, L. D. S., D. D. S., M. D., 

Professor of Operative Dentistry and Dental Pathology in the 
Royal College of Dental Surgeons of Ontario; Editor of "The 
Dominion Dental Journal," etc. 

GEORGE H. WRIGHT, D. M. D., 

Former Assistant in Embryology and Histology, Harvard Medi- 
cal School. 



A TEXT-BOOK OF 



OPERATIVE DENTISTRY 



BY VARIOUS AUTHORS 



EDITED BY 

C. N. JOHNSON, M. A., L. D. S., D. D. S. 

PROFESSOR OF OPERATIVE DENTISTRY IN THE CHICAGO COLLEGE OF DENTAL SURGERY; 
EDITOR OF THE "DENTAL REVIEW" 



WITH SIX HUNDRED AND EIGHTEEN ILLUSTRATIONS 



PHILADELPHIA 

P. BLAKISTON'S SON & CO. 

1012 WALNUT STREET 

1908 



^ 



LIBRARY of CONGRESS? 
I WO COD»es Hece.xs? 

SEP 8 1SHW 

Wtfttfi Km CnuJ 

CLASS <<X AAfc «„. 

aopt a/ * 



Copyright, 1908, by P. Blakistox's Sox & Co. 



Printed by 

The Maple Press 

York, Pa. 



PREFACE 



In preparing this book for the profession the aim has been to 
condense the latest thought on the various subjects into the closest 
possible limit consistent with a clear elucidation of the ideas presented. 
It has been the constant effort to bring the work strictly up to date, 
and with the rapid evolution of dental thought in progress at the 
present time this has been no small task. As an illustration it is only 
necessary to mention the circumstance that one entire chapter — that 
by Dr. Nyman on the gold inlay — was wholly rewritten after it was 
in type and the illustrations made for it. The original article was 
discarded as being out of date the moment the cast method became a 
demonstrated fact. This is only indicative of the great care taken by 
the various authors in the revision of their work, and for which the 
editor wishes at this time to express his great appreciation. 

Particular attention is called to the illustrative character of the 
work. Most of the cuts were made specially for the book, and many 
of them are striking in their originality. Those, for instance, illustrating 
Dr. Turner's chapter on "The Anatomy of the Human Teeth" were 
made from photographs of natural teeth, a typical specimen of each 
tooth being selected for this purpose and photographed on its different 
surfaces. The effect has been to present something perfectly true to 
nature. 

Mention might be made of distinguishing features in each chapter 
in the book, but this would appear unnecessary with the work in the 
reader's hands. It seems appropriate, however, to call attention to 
Dr. Pullen's chapter on "Orthodontia" which we believe is one of 
the most concise and practical presentations of this important subject 
that has yet appeared. 

To the contributors the editor feels under deep obligation for their 
cordial cooperation in preparing the work, and to the publishers 
for their uniform courtesy and painstaking care in every detail of 
publication. C. N. J. 

Chicago, August, 1908. 



CONTENTS. 



PAGE 

Introduction, xi 

BY C. N. JOHNSON, M. A., L. D. S., D. D. S. 

CHAPTER I. 

The Anatomy of the Human Teeth, i 

BY CHARLES R. TURNER, D. D. S., M. D. 

CHAPTER II. 

The Histology of the Human Teeth, 59 

BY CHARLES R. TURNER, D. D. S., M. D. 

CHAPTER III. 

Hygiene and Arrangement of Light in the Operating Room, 85 

BY C. N. JOHNSON, M. A., L. D. S., D. D. S. 

CHAPTER IV. 

Asepsis in the Operating-Room 89 

BY A. E. WEBSTER, M. D., L. D. S., D. D. S. 

CHAPTER V. 

Hygiene of the Mouth, 97 

BY GEORGE H. WRIGHT, D. M. D. 

CHAPTER VI. 
Dental Caries, 117 

BY C. N. JOHNSON, M. A., L. D. S., D. D. S. 

CHAPTER VII. 

Examination of Teeth for the Finding of Carious Cavities, 127 

BY GARRETT NEWKIRK, M. D. 

CHAPTER VIII. 

Separation of Teeth Preparatory to Operating on Cavities in the Proximal 

Surfaces, 133 

BY GARRETT NEWKIRK, M. D. 

CHAPTER IX. 

Exclusion of Moisture from the Teeth during Operations, 145 

BY GEORGE EDWIN HUNT, M. D., D. D. S. 

vii 



y|ii CONTENTS. 

CHAPTER X. 
Preparation oi Cavities for Fillings 161 

BY A. E. WEBSTER, M. D., L. D. S., D. D. S. 

CHAPTER XI. 

The Treatment of Sensitive Dentin, 215 

BY J. P. BUCKLEY, PH. G., D. D. S. 

CHAPTER XII. 

Filling Materials: Their Characteristics, Indications for Their Use and the 

Methods of Manipulation, 225 

BY ALFRED OWRE, M. D., C. M.,.D. M. D. 

CHAPTER XIII. 

The Use of the Matrix in Filling Teeth, 255 

BY GARRETT NEWKIRK, M. D. 

CHAPTER XIV. 
Inlays 263 

BY C. N. JOHNSON, M. A., L. D. S., D. D. S. 

CHAPTER XV 

Preparation of Cavities for Inlays, 267 

BY C. N. JOHNSON, M. A., L. D. S., D. D. S. 

CHAPTER XVI. 

The Porcelain Inlay, 277 

BY W. A. CAPON. D. D. S. 

CHAPTER XVII. 

Construction of Gold Inlays, 301 

BY JOHN EGBERT NYMAN, D. D. S. 

CHAPTER XVIII. 

The Treatment of Exposed or Nearly Exposed Pulps, 311 

BY J. P. BUCKLEY, PH. G., D. D. S. 

CHAPTER XIX. 

The Anesthetization and Devitalization of Pulps, Their Removal and the 

Subsequent Treatment, 317 

BY J. P. BUCKLEY, PH. G., D. D. S. 

CHAPTER XX. 

The Treatment of Ordinary Pericementitis, 335 

BY J. P. BUCKLEY, PH. G.. D. D. S. 

CHAPTER XXI. 

The Chemistry of Pulp Decomposition, 341 

BY J. P. BUCKLEY, PH. G., D. D. S. 



CONTENTS. IX 

CHAPTER XXII. T , APV 

The Treatment of Putrescent Pulps; Acute and Chronic Alveolar Abscess, 

with Complications; and the Filling of Root Canals, 347 

BY J. P. BUCKLEY, PH. G., D. D. S. 

CHAPTER XXIII. 

The Causes and Treatment of Discolorations of Teeth, 367 

BY J. P. BUCKLEY, PH. G., D. D. S. 

' CHAPTER XXIV. 

The Treatment of Children's Teeth, 377 

BY C. N. JOHNSON, M. A., L. D. S., D. L\ S. 

CHAPTER XXV. 
Local Anesthesia, 385 

BY HERMANN PRINZ, M. D., D. D. S 

CHAPTER XXVI. 
The Extraction of Teeth, 399 

BY FERDINAND J. S. GORGAS, A. M., M. D., D. D. S. 

CHAPTER XXVII. 
The Planting of Teeth, 439 

BY C. EDMUND KELLS, JR., D. D. S. 

CHAPTER XXVIII. 

Pyorrhea Alveolaris, 451 

BY JOHN DEANS PATTERSON, D. D. S. 

CHAPTER XXIX. 
Erosion, 471 

BY GEO. W. COOK, D. D. S. 

CHAPTER XXX. 
The Management of an Office Practice, 483 

BY ELLISON HILLYER, D. D. S. 

CHAPTER XXXI. 

Orthodontia, 505 

by herbert a. pullen, d. m. d. 

Index ... ' - 747 



INTRODUCTION 



Operative Dentistry may be denned as the science and art which 
aims at the preservation of the natural teeth in a state of health and 
beauty. Its highest office is to prevent disease or deformity, but 
where either of these has already occurred it is then its function to 
remedy the evil, and check its further progress. The dentist who 
does the best for his patient is the one who, in addition to the develop- 
ment of the highest manipulative skill, studies most carefully the 
conditions surrounding the field of his operations. To fill a cavity 
in a tooth in the most perfect manner possible, when the surrounding 
tissues are in an abnormal condition, without a recognition of this 
fact and the most careful attention to the abnormality, is far from 
good practice. To attempt to remedy any disorder in the mouth by 
confining attention solely to the immediate seat of the trouble is fre- 
quently to court failure. The human economy is so complicated that 
cause and effect are often remote from each other, and the practitioner 
who does the best service to his patient is the one who in addition 
to being an acute observer extends his observation over the widest 
field. 

The conscientious dentist, when he finds himself baffled in dis- 
covering the cause or relieving the symptoms of any affection of the 
mouth will not hesitate to call in consultation a specialist in dentistry 
or medicine as the case indicates, and particularly is it desirable in 
instances of peculiar idiosyncrasies to consult with the family physician 
of the patient. 

No individual practicing a profession like dentistry should think 
lightly of his obligations, and no practitioner can properly fulfil his 
obligations without developing the habit of painstaking care in all 
his work whether of diagnosis or treatment. It should early be 
recognized by the young practitioner that dentistry demands of those 
who aim to excel in its practice a more diversified order of talent than 
any other calling. To be a good dentist an individual should develop 
the scientist's attitude toward the intimate and sometimes intricate 
relationship between cause and effect, he should be a close observer 
of phenomena, a mechanician of the first order, an artist with the sense 

xi 



xii INTRODUCTION. 

of harmony highly cultivated, a physician in his diagnosis of disease, 
a humanitarian in his ministrations to others, and above all a cultured 
gentleman of the highest mental and moral fiber. 

This does not imply that in the beginning he must be endowed 
with great brain capacity or natural attributes of an unusual char- 
acter. The encouraging thing about dentistry is that most of the 
qualities necessary for achievement are capable of cultivation, and 
the man who will apply himself with sufficient zeal and perseverance 
is certain of at least a reasonable measure of success. The chief 
requisite is the patience to plod. 

If every dentist would bring to his work a real sincerity of purpose 
to serve his patients to the highest possibilities of his art, the future 
of the profession would be secure. There would be less need than 
there is today of artificial teeth, and the full functional use of the 
natural organs in mastication and in harmony of expression would 
be more generally recognized and appreciated. As we develop 
dentistry along the lines of prevention and conservation we shall 
bring it nearer and nearer to its highest mission. To do the greatest 
good to the largest number, to do this good without thought of self 
advancement, to work for the love of it and for the benefit it brings 
to humanity — this is the acme of faithful service and the only kind of 
effort which will bring permanent satisfaction. Unless a dentist is 
willing to do this he will fall short of all that his profession has to offer 
him, if he does it he may be certain of an encouraging measure of 
attainment. 

But to accomplish anything of note he must be progressive. The 
methods of yesterday will not suffice for today. No profession is 
developing more rapidly than dentistry and he who would give the 
best service must ever be alive to the latest advances. The foremost 
thinkers of the profession are constantly placing their ideas before 
their fellow practitioners, and the man who keeps abreast must be 
alert to avail himself of the results of their matured thought. It is 
with the purpose of presenting this thought in the most condensed 
form as it relates to the different departments of operative dentistry 
that the present volume is issued. 



OPERATIVE DENTISTRY. 



CHAPTER I. 
THE ANATOMY OF THE HUMAN TEETH. 

BY CHARLES R. TURNER, D. D. S., M. D. 

The teeth of man are hard masses of calcified tissue attached to 
the mandible and maxilla and having as their chief function partici- 
pation in the work of his masticatory apparatus. His food, as intro- 
duced into the mouth, the beginning of the digestive tract, consists of 
articles of various degrees of physical consistency. In order that 
this may be prepared for subsequent stages in the digestive process, 
much of it must be mechanically subdivided into particles of convenient 
size to go through the alimentary canal and be acted upon by the di- 
gestive ferments and solvents. Such subdivision is performed in the 
mouth by the act of mastication and it is with this function that the 
teeth are chiefly concerned. They afford hard opposed surfaces 
which are brought into contact in the approximation of the jaws by 
the muscular apparatus and by this means the food is cut or crushed 
into particles of the desired size. 

The teeth also have a functional relationship with the apparatus 
by which voice and speech are produced and bear a cosmetic relation 
to the features of the face. 

The adult human denture consists normally of thirty-two teeth 
which are divided in number equally between the upper and the lower 
jaw. These are known as the permanent teeth, in contra-distinction 
to the temporary or deciduous teeth which serve for purposes of mas- 
tication during the earlier years of life and are subsequently exfoliated 
to give place to their permanent successors. 

The permanent teeth are divided anatomically into classes and 
these divisions largely correspond with their functions as portions 
of the masticatory apparatus. Thus, there are eight incisors, which 

Note. — The author desires to acknowledge his indebtedness for Figs, i to 84 inclu- 
sive to Dr. George J. Paynter, of the Department of Dentistry, University of Pennsyl- 
vania, who selected and dissected the specimens, and to the Department of Dentistry, 
University of Pennsylvania, for whom the photographs were made, for permission to 
reproduce them. 



THE ANATOMY OF THE HUMAN TEETH. 

servo in the incising of the food; four cuspids, whose chief function 
in the carnivorous animals is to pierce and hold the food, a function 
wholly rudimentary with man; eight bicuspids, which are intermedi- 
ate in position and function between the cuspids and the molars, 
and lastly twelve molars which are the crushing and grinding teeth 
proper. The formula for the permanent human dentition is expressed : 

!« c™, B 2=?, M»-j. 

2-2 I-I 2-2 3-3 

The deciduous denture consists of twenty teeth — eight incisors, 
four cuspids and eight molars. 

As all the teeth possess certain characteristics in common it will 
be well to refer to these before undertaking a description of the in- 
dividual teeth. 

The crown of a tooth is that portion which projects beyond the 
gum margin and is normally covered with enamel. The root or roots 
of the tooth are imbedded in the alveolar process and are attached 
thereto by a fibrous membrane, the pericementum. The root and 
crown of a tooth unite at its neck, a point which corresponds to the 
point of juncture of the enamel and the cementum. This is also called 
the cervix and also the gingival margin of the crown. The sharp- 
ened extremity of a root is known as its apex, and this is the seat of an 
opening which transmits the nerves and blood vessels of the pulp of the 
tooth and is known as the apical foramen. The surface of a tooth 
which comes into contact with the corresponding surface of teeth 
in the opposing jaw is referred to as the occlusal surface. This term 
is also applied to the analogous portion of the incisor teeth although 
strictly speaking it should only apply to that of the lower incisors, in- 
asmuch as this edge of the incisors of the upper jaw does not touch 
the teeth of the lower jaw, when the teeth are in occlusal contact, but 
normally is only brought into this relationship when the mandible is 
protruded. This is also referred to as the incisive edge of the incisors. 
Molar and bicuspid teeth have large tubercles upon their occlusal 
surfaces and these are known as cusps. The adjoining surfaces of 
teeth are known as their proximal surfaces, the most prominent point 
of which is called the angle of the tooth. If a vertical plane is passed 
between the central incisors of both jaws, those proximal surfaces of 
the teeth which are directed toward this are known as mesial surfaces, 
while those proximal surfaces directed away from it are known as 
distal surfaces. The surfaces of the six anterior teeth of each series 
which are in relation with the lips are called labial, while the corre- 



THE UPPER CENTRAL INCISOR. 3 

sponding surfaces of the remaining teeth which are in relation with the 
cheeks are called buccal surfaces. Those surfaces of the teeth which 
are directed inward toward the cavity of the mouth are known as their 
lingual surfaces. 

The surface-form and internal anatomy of the permanent teeth 
will now be given in detail. 

THE UPPER CENTRAL INCISOR. 

The crown of this tooth is wedge-shaped; the base of the wedge 
is at its cervical margin from which the broad labial and lingual sur- 
faces converge to a straight cutting edge. 





Fig. 1. 



-Left Upper Central Incisor. 
Labial Surface. 



Fig. 



2. — Left Upper Central Incisor. 
Lingual Surface. 



The Labial Surface (Fig. 1). — Irregularly quadrilateral in shape, 
this surface has four margins. The incisive edge which forms its 
lower margin is nearly straight; it is marked in the newly erupted 
tooth by two developmental grooves which disappear early in life be- 
cause of the wearing down of the three tubercles which are found on 
this edge. The mesial margin is nearly straight or may be a long 



4 I'HK ANATOMY OF THE HUMAN TEETH. 

curve; the cervical border is convex rootward, while the distal margin 
is more convex than the mesial and is a little shorter. The surface 
itself is convex from the cervix to the incisive edge, the lower portion 
oi it being, however, nearly flat, while that portion near the cervix is 
more curved and is marked by a cervical ridge. This face of the crown 
is convex from side to side and is marked by two longitudinal grooves 
which correspond to the lines of union of the three developmental lobes 
of the crown. 

The Lingual Surface (Fig. 2).— This is irregularly triangular, the 
mesial and distal margins uniting with the cervical to form a rounded 





Fig. 3. — Left Upper Central Incisor. 
Mesial Surface. 



Fig. 



4. — Left Upper Central Incisor. 
Distal Surface. 



apex, while the base of the triangle is formed by the incisive margin. 
The mesial and distal margins are marked by rounded ridges of enamel 
which extend from the angles of the crown in a graceful curve rootward 
to unite with the cervical ridge. The mesial is slightly the longer of 
these two. The cervical is more pronounced than the other marginal 
ridges. It is sometimes cut near its center by a fissure and sometimes 
it is the seat of a rounded elevation of enamel, the cingulum. The 



THE UPPER CENTRAL INCISOR. 



5 




Fig. 5.— Left Upper Central 
Incisor. Occlusal View. 



lingual surface is concave occluso-gingivally and mesio-distally. Its 

center is occupied by a pronounced fossa, the lingual fossa, which is 

traversed by two longitudinal grooves. 

Occasionally a lingual pit is present and 

this occupies a position at the juncture of 

the cervical ridge and the lingual fossa. 
The Mesial Surface (Fig. 3). — Being 

shaped like a spear-head or irregularly tri- 
angular in outline, this surface has three 

margins. The labial presents a long curve 

ending in the mesial angle of the tooth and 

is shorter than the lingual which it meets at 

this point. Both are bowed in a labial 

direction and the labial margin is the more pronounced, the lingual 

being rounded and marking less distinctly the boundary of the surface. 

The cervical margin is concave in an oc- 
clusal direction and at its terminations 
unites with both the labial and lingual bor- 
ders at an acute angle. Near the incisive 
edge the surface is convex but this convex- 
ity decreases as the root is approached and 
the surface becomes either a plane or is 
marked by a slight depression at the gingival 
margin. The most prominent point of the 
surface is located one-third the distance 
from the mesial angle and this establishes 
the point of contact with the central incisor 
of the opposite side. 

The Distal Surface (Fig. 4). — While 
this is of the same general shape as the 
mesial surface, it is slightly smaller because 
of the location of the distal angle nearer to 
the cervix. Its margins are less distinct 
and the surface is more rounded and the 
poin!: of contact with the lateral is relatively 
nearer the cervix. 

The Incisive Edge (Fig. 5). — The in- 
cisive edge is formed by the intersection 
of the planes of the labial and lingual sur- 
These do not meet at an acute angle but their 




Fig. 6. — Left Upper Central 
Incisor. Longitudinal section 
cut labio-lingually showing 
pulp cavity. 



faces of the crown. 

line of intersection is somewhat rounded. 



This edge extends from 



IH1 ANATOMY OF THE HUMAN TEETH. 



the mesial to the distal angle, usually almost in a straight line. In 
voting subjects it is marked by the developmental grooves, but these 

usually disappear from the wearing of the 
surfaces. When the crown is viewed from 
below, the line of the incisive edge is oc- 
casionally bowed in a labial direction. 

The Cervical Margin. — Beginning at the 
mesio-labial portion of this line, it extends 
with an upward curve upon the labial sur- 

face, downward on the distal upward on 

Fig. -.— Left Upper Central the lingual, and downward again on the 

Incisor. Cross-section at cer- . , ,-, • , r 1 T , ■ 

vix showing pulp chamber in mesial to the point of beginning. It IS 
crown. Looking crownward. marked by the bulging of the cervical ridge 
on the labial and lingual surfaces. While there is usually a well- 
defined constriction on the tooth at this 
point, the neck of the tooth is not so marked 
as in some of the distal teeth. 

The Root. — This is conical in shape, 
and when viewed from the labial surface 
(Fig. 1) its sides converge in almost straight 
lines to a rounded point; but viewed from 
the mesial (Fig. 3) or distal side the outlines 
of the root curve to a rounded point. When 
viewed in cross-section at the neck the labio- 
lingual diameter of the root is greater than in °] d tooth - Looking crown- 

° ward. 

the mesio-distal and the root outline is that 

of a rounded triangle with its sides corresponding to the labial, mesial, 
and distal faces of the root. Of these the 
mesial is the longest and nearly straight, the 
labial and lingual being approximately equal in 
length but the labial is the most curved of all. 
The Pulp Cavity. — The form of the pulp 
cavity of the central incisor corresponds in 
general with the external form of the tooth 
itself (Fig. 6). It is divisible into the pulp 
chamber and the pulp canal, but the line of 
division is not clearly marked. The pulp 
chamber occupies the crown of the tooth and, 
as seen in a labio-lingual section of the tooth 

(Fig. 6) follows the form of the crown closely. The pulp canal is 

conic in form, with its base joining the pulp chamber and its apex 




Fig. 8. — Left Upper Central 
Incisor. Cross-section at cer- 
vix showing small pulp cavity 




Fig. 9.— Left Upper Cen- 
tral Incisor. Cross-section 
made at middle of crown 
(looking rootward) showing 
form of pulp chamber. 



THE UPPER LATERAL INCISOR. 7 

reaching the apex of the root where it terminates in the apical 
foramen. In a mesio-distal section of the tooth the flattening out of 
the occlusal end of the pulp chamber to follow the incisive edge of the 
tooth, is seen. (Fig. 9.) The portions extending in the direction of 
the angles of the tooth are known as the " horns" of the pulp. In the 
young subject there are three concavities in its occlusal end, correspond- 





Fig. 10. — Right Upper Lateral Incisor. Fig. ii. — Right Upper Lateral Incisor. 

Labial Surface. Lingual Surface. 

ing to the three tubercles and the three developmental centers of the 
incisive edge of the crown. A cross-section of the root at the cervix 
shows the pulp cavity almost circular in outline (Fig. 7), and this form 
characterizes it to the end of the root. The pulp cavity of this, as of 
all the teeth, diminishes in size from the time of completion of the root 
through old age because of the deposit of dentin upon its walls (Fig. 8). 

THE UPPER LATERAL INCISOR. 

The Labial Surface (Fig. 10). — This surface is somewhat similar in 
outline to that of the central incisor except that it is smaller, being 
narrower from side to side and shorter, and its distal angle is more 
rounded. It is bordered by four margins. The incisive margin is 






THE ANATOMY OF THE HUMAN TEETH. 



almost straight, being, however, inclined slightly downward in the 
direction oi the median line and in the young tooth is marked by 
developmental grooves which are less prominent than those of the 
central incisor. The mesial margin is nearly straight from the mesial 
angle to the cervix, being sometimes, however, slightly concave which 
causes a hook-like appearance to this surface of the tooth. The cer- 
vical margin is markedly convex rootward since the tooth is narrower 
than the central incisor, while the distal margin is also made convex 





Fig. 12 



-Right Upper Lateral Incisor. 
| Mesial Surface. 



Fig. 



13. — Right Upper Lateral Incisor. 
Distal Surface. 



from the projection of its distal angle. The latter is longer than the 
mesial margin cicumferentially, but a straight line drawn from the 
distal angle to the cervix show-s that this portion of the face is shorter 
than the mesial portion. The labial surface is more rounded in every 
way than that of the central. The cervical ridge and developmental 
grooves are present but are not so pronounced. 

The Lingual Surface (Fig. n). — Like that of the central incisor, 
this surface is usually slightly concave, which is due to the projection 
of the mesial, distal and cervical marginal ridges. In outline it is 
nearly triangular. The incisive margin is the same shape as that de- 



THE UPPER LATERAL INCISOR. 9 

scribed for the labial surface. The mesial and distal marginal ridges 
are well marked and unite with the cervical. Both the mesial and 
distal margins are usually convex although the mesial may be almost 
straight. The distal is much shorter. The cervical margin is formed 
by the cervical ridge and is more frequently the seat of a cingulum 
than that of the central incisor. While the surface is usually con- 
cave in all directions, in some instances it may be almost flat. There 
is normally a well-defined fossa and in some cases this latter is marked 
with a longitudinal ridge corresponding to that on the labial face. 

The Mesial Surface (Fig. 12). — Shaped like an arrow-head, the 
cervical margin being concave, the labial margin of this surface is con- 
vex with a long curve. The lingual margin is less distinctly marked, is 
concave, and unites with the labial at the mesial angle of the crown. 
The surface is convex in its lower two-thirds 
but becomes flattened toward the cervix where 
sometimes a pronounced depression may exist. 
The point of contact with the central is about 
one-third the distance from the cutting edge. 

The Distal Surface (Fig. 13). — This has the 
same general outline as the mesial but is more 
rounded in every way. The cervical margin is fig. 14.— Right Upper 
similar to that on the mesial face but the labial L ^ al Incisor - ° cclu - 

sal \ lew. 

and lingual are shorter, meeting at the distal 

angle which is less sharp and nearer the gingival margin than the 
mesial angle. The prominence of this surface makes this tooth quite 
different from the other incisors and it is more nearly the shape of 
that of the cuspid with which it is in contact. 

The Cervical Margin^ — Although like the central in general char- 
acteristics, the labial and lingual portions of this line are more convex 
rootward, the latter being a sharper curve and extending proportion- 
ately higher than the labial. The mesial and distal portions are con- 
cave rootward, are similar in general form, and are quite angular. 

The Incisive Edge (Fig. 14). — This is proportionately shorter than 
that of the central, is often a nearly straight line between the angles 
of the crown and is usually slightly curved in a labial direction as the 
tooth, is viewed from below. Like the central incisor, at the time of 
its eruption it displays usually three developmental tubercles which 
indicate the three points at which calcification begins, but these are 
soon worn off. 

The Root. — The root of the lateral incisor has a general conical 
form, is often slightly longer than that of the central incisor, and is 




IO 



THE ANATOMY OF THE HUMAN TEETH. 



flattened mesio-distally. Its extremity usually has a slight distal bend. 
At the neck of the tooth it is almost circular in cross-section and is 
again at the apex, but the intervening portion exhibits the flattening 
above referred to and in some instances pronounced grooves upon the 
mesial and distal surfaces. In the center of its length the root is ap- 
proximately one-third greater in labio-lingual diameter than mesio- 
distally. 

The Pulp Cavity.— This corresponds in form to that of the tooth 
and differs but little except in size from that of the central incisor. 





Fig. 15. — Right Lower Central Incisor. 
Labial Surface. 



Fig. 16.— Right Lower Central Incisor. 
Lingual Surface. 



THE LOWER CENTRAL INCISOR. 

This is the smallest tooth in the mouth. Its crown is wedge-shaped 
(Fig. 17). 

The Labial Surface (Fig. 15). — In outline this face of the crown is 
nearly triangular, the incisive margin being the base while the mesial 
and distal margins converge to the rounded apex formed by the cervical 
margin. The incisive edge is nearly straight and almost at right angles 
with the long axis of the tooth. The mesial and distal margins are 



THE LOWER CENTRAL INCISOR. II 

long curves, the distal being very slightly shorter and more curved. 
The cervical border is very short; the surface is convex from incisive 
edge to cervix, and, when seen in profile, almost exactly the arc of a 
circle. Near the incisive edge the surface is nearly straight, the di- 
vision between it and the mesial distal surfaces being marked by fairly 
well-defined angles; as the cervix is approached, however, it becomes 





Fig. 17. — Right Lower Central Incisor. Fig. 18. — Right Lower Central Incisor. 
Mesial Surface. Distal Surface. 



more rounded. Like the upper incisors it is sometimes marked by 
two developmental grooves but these are normally poorly discernible 
except in young teeth. 

The Lingual Surface (Fig. 16). — Like the labial this is nearly 
triangular in outline but the rounded apex formed by tbe cervical 
margin is more nearly an acute angle. The surface is concave from 
incisive margin to the cervical ridge when this latter causes it to be 
marked with a convexity which ends abruptly by a well-defined margin 
at the neck of the tooth. The mesial and distal marginal ridges are 
usually poorly defined, the cervical ridge in which they unite corre- 
sponding with them in this particular except that it is usually somewhat 



12 



THE ANATOMY OF THE HUMAN TEETH. 



more easily traced. The occlusal third of this surface is usually slightly 
bowed in a labial direction, making it concave mesio-distally, but this 
concavity gradually disappears before the center 
of the surface is reached. 

The Mesial Surface (Fig. 17). — This is tri- 
angular in outline, but unlike the labial and 
lingual surfaces the base of the triangle is 
^^^^*f directed rootward and is formed by a concave 

cervical margin. The sides of the triangle 

' ' formed by the labial -and lingual margins are 

Fig. 19.— Right Lower curved, in a labial direction, the labial being 
Central Incisor. Occlusal s h orter an d more curved and meeting the lingual 

at the mesial angle of the tooth. This surface is 
slightly convex, being most markedly so at its center just above which 
point it is in contact with its fellow of the opposite side. 

The Distal Surface (Fig. 18). — This is 
similar in outline and contour to the mesial 
surface, except that it is slightly shorter and is 
more convex in its incisive third because the 
labial and lingual margins meet in a more 
rounded eminence the distal angle. Near the 
cervical margin it is often slightly concave, in 
which instance the concavity in commonly 
continued up the 'root as a longitudinal de- 
pression. 

The Incisive Edge (Figs. 15 and 19). — 
Like those of the upper jaw the lower central 
incisor at the time of its eruption is usually 
characterized by the presence of three tuber- 
cles upon its incisive edge. These are soon 
worn off and the edge is then straight. It 
occupies a line at right angles to the long axis 
of the tooth, terminating in the mesial and 
distal angles of which the former is slightly 
the more pronounced. 

The Cervical Margin. — This is similar in 
outline to that of the upper incisors except 
that it is more angular. On the mesial and 
distal surfaces it is markedly concave in the 
direction of the crown and extends rootward on the lingual and the 
labial surface. The lingual portion is short and angular, which 




Fig. 20. — Right Lower 
Central Incisor. Labio- 
lingual longitudinal section 
showing bifurcation of pulp 
canal. 




THE LOWER LATERAL INCISOR. 13 

latter characteristic is caused by the projscti3n downward of the 
abrupt cervical ridge of this surface of the crown. The labial portion 
of the cervical margin is concave rootward but less sharply so than the 
lingual. 

The Root. — The root on this tooth is more delicate than that of any 
other in the mouth. It is conical in shape, being much flattened upon 
its mesial and distal sides (Figs. 17 and 18) at the cervix from which 
point these surfaces slope in almost straight lines to the apex. This 
latter is sometimes slightly deflected in a distal direction. These sides 
of the root are frequently marked with longitudinal grooves which ex- 
tend almost to the apex. The labial and lingual 
aspects of the root are narrow, the former being 
the wider and they converge gradually to within a 
short distance of the apex when they rapidly ap- 
proach each other and give the root a rounded ap- 
pearance which is observed when it is viewed from 
the mesial or distal side. The labial surface of the 
root continues the line of that surface of the crown, 
making with it almost a perfect arc of a circle. Lower ^en^a? 1 !]!- 

The Pulp Cavity. — This cavity follows the cisor. Cross-section of 
, r r , . . tit crown near its middle 

general form of the exterior of the tooth and only looking rootward. 
a few points need to be touched upon in its de- 
scription. The horns of the pulp chamber extend well toward the 
mesial and distal surfaces, but the cavity is very narrow labio-lingually 
at its extremity. There is no perceptible line of division between this 
and the pulp canal. The latter is flattened and narrow in its beginning 
at the cervix (Fig. 20) and occasionally divides into two canals which 
usually unite near the apex and terminate in a single foramen. In 
most instances, however, it exists as a small, slightly flattened canal. 

THE LOWER LATERAL INCISOR. 

This tooth so nearly resembles the lower central incisor that sepa- 
rate description seems superfluous, therefore only its differentiating 
characteristics will be pointed out. It is wider mesio-distially than 
the lower central incisor; its distal angle is more rounded and its distal 
surface slightly more convex. Its root is somewhat longer than that 
of the lower central incisor and at its apex is often bent distally. The 
pulp chamber is similar in all respects to that of the lower central in- 
cisor except that it is slightly larger in its coronal portion in corre- 
spondence with the greater size of the crowm. 



M 



THE ANATOMY OF THE HUMAN TEETH. 



THE UPPER CUSPID. 

The crown of this tooth presents for examination four surfaces and 
a cusp. 

The Labial Surface (Fig. 22). — The outline of th's surface 
shows that it is bounded with five margins. The incisal portion 
provides two, the mesial and distal incisive edges. The former of 
these [extends from the point of the cusp to the mesial angle, 
being] either concave because of the presence of a developmental 





Fig. 22. — Right Upper Cuspid. 
Labial Surface. 



Fig. 23. — Right Upper Cuspid. 
Lingual Surface. 



groove or it may be slightly convex. The distal incisive margin which 
extends from the cusp to the distal angle is usually longer than the 
mesial incisive and more frequently marked with a slight convexity. 
The wearing down of the cusp in adult teeth usually results in making 
the point of separation between these margins less distinct. The 
mesial margin of the labial surface is convex, as is also the distal w T hich 
descends from the distal angle of the crown. The cervical margin 
follows very much the same curve as that of the central incisor, the 
highest portion of its convexity, however, being a little nearer its mesial 



THE UPPER CUSPID. 



15 



end. The surface is convex from cusp to cervix and also from the 
mesial to the distal angle but is sometimes marked by two longitudinal 
developmental grooves. These, beginning nearer the mesial and distal 
angles than the cusp of the crown, ascend toward the cervix, gradually 
disappearing about the upper third of the surface. The labial ridge 
ascends from the cusp, being located nearer the mesial than the distal 
surface of the crown, and gradually blends with the rounded convexity 
of the upper third of this surface. When the developmental grooves 





Fig. 



24. — Right Upper Cuspid. 
Mesial Surface. 



Fig. 25. — Right Upper Cuspid. 
Distal Surface. 



are not marked the labial surface mesial to the ridge is more convex 
than that distal to it. 

The Lingual Surface (Fig. 23). — With much the same outline as 
the labial face, this surface is slightly smaller, but is proportionately 
longer from cusp to cervix, and has a shorter and more convex cervical 
margin. The surface has a general convexity and is marked by a 
lingual ridge which ascends from the cusp and does not fade away 
until it reaches the cervical marginal ridge. It corresponds in posi- 
tion to the labial ridge of the opposite face of the crown. In dis- 
tinctly marked teeth there is a groove on either side of this ridge. 



10 



THE ANATOMY OF THE HUMAN TEETH. 




Fig. 



>6. — Right Upper Cuspid. 
Occlusal View. 



The cervical marginal ridge is usually a pronounced, rounded eleva- 
tion affording a distinct line of demarcation between the crown and 

root of this tooth. It is frequently the seat 
of an elevation at or near its center, and 
may have a fissure dividing the ridge on 
either or both sides of the cingulum. The 
mesial and distal marginal ridges are less 
well marked than the cervical from which 
they extend to the mesial and distal angles 
of the crown. The mesial is the longer and 
better defined. 

The Mesial Surface (Fig. 24). — Shaped 
like an arrow-head, the labial boundary 

convex and the lingual usually concave, the outline of this surface is 

completed by the concave cervical margin. The highest portion of this 

latter is slightly nearer its junction with the 

labial than with the lingual margin. The 

mesial angle which is the meeting ground of 

the labial and lingual margins is just below 

the point at which this tooth is in contact with 

the lateral incisor. It is not quite so near the 

cervix as is the distal angle. The surface is 

nearly convex in its lower two-thirds but above 

this point may be flat or slightly concave. 
The Distal Surface (Fig. 25). — This is 

similar in shape to the mesial but is some- 
what smaller in extent and more convex. 

The distal angle is more protuberant than the 

mesial and just above it is a rounded point 

with which the tooth is in contact with the 

first bicuspid. The cervical margin is less 

concave than the mesial and its highest 

portion is nearer the labial than the lingual 

margin. 

The Cusp (Fig. 26). — This is the prominent 

point of the cutting edge and is formed by the 

union of the mesial and distal cutting edges 

and the labial and lingual ridges. It is sharp 

in well-marked teeth at the time of eruption 

but the point is soon worn down and may be blunt or rounded. 

-Convex labially and lingually and concave 




Fig. 27. — Right Upper 
Cuspid. Longitudinal sec- 
tion cut antero-posteriorly 
showing pulp cavity. 



The Cervical Margin. 




THE LOWER CUSPID. 1 7 

mesially and distally, this margin corresponds closely to that of the 
upper central incisor. 

The Root. — Like that of all single-rooted teeth the root of the 
upper cuspid is conical. On all its four sides it gradually tapers 
from the cervix to the apex. In cross-section at the cervical margins 
(Fig. 28) it is ovoid or may be almost circular. In the former instance 
the labial side is the segment of a larger circle 
than the lingual. The mesial and distal 
aspects of the roots are often flattened, in 
which case their centers sometimes present 
poorly marked longitudinal grooves. At the 
apex the root is usually inclined in a distal 
direction or the whole root may have a slight 
distal curve. 

The Pulp Cavity (Figs. 27 and 28). — In 
the young tooth there is a pronounced pro- Fig. 28.— Right Upper Cus- 

. pid. Cross-section at cervix 

jection of the pulp chamber wall toward the looking crown ward, showing 
cusp of this tooth, but as it becomes more shape of pulp cavity " 
mature the pulp cavity becomes more flattened here. Otherwise it is 
very much like the external form of the tooth, extending well toward 
the mesial and distal angles, and closely resembling that of the central 
incisor. At the level of the cervix it is oval in cross-section and ex- 
tends gradually diminishing in size to the apex. There is no line of 
demarcation between the root and coronal portion of the cavity. 

THE LOWER CUSPID. 

The crown of the cuspid of the lower series is very similar to that 
of its upper, except that it is narrower, more delicate and slightly longer, 
and usually not so well marked. 

The Labial Surface. — The markings of this surface are not so pro- 
nounced as those of the upper cuspid. The outline is less angular 
than that of the upper, with the exception of that portion formed by 
the mesial and distal incisive edges, for its cusp is more pointed than 
that of the upper cuspid. The developmental grooves are usually 
poorly defined, the labial ridge being the most prominent mark- 
ing of this surface and giving to it a marked convexity. This ridge, 
as in the upper cuspid, is located decidedly nearer the mesial than the 
distal margin. The mesial margin is more pronounced than the distal, 
the labial surface meeting the mesial somewhat more abruptly than 
the distal into which it passes by a rounded curve without definition. 



lS THE ANATOMY OF THE HUMAN TEETH. 

The Lingual Surface. — The outline is more rounded and the sur- 
face markings less bold than those of the upper cuspid. The marginal 
ridges are usually poorly defined, that at the cervix being more prom- 
inent than the mesial or distal. The lingual ridge extends from the 
cusp to the cervix, dividing this surface and forming two very shallow 
grooves or fossae, the lingual grooves; but the- surface is less convex 
than that of the upper, especially at the occlusal end, which is some- 
times flat mesio-distally. 

The Mesial Surface. — Similar in shape to that of the upper, yet 
differing from it in some particulars, this surface of the lower cuspid 
possesses the peculiarity of being almost flat and being continuous 
as an almost plane surface with the root. At the cervix it is slightly con- 
cave or it may be simply flat, but it assumes a convex character as the 
mesial angle is approached. The cervical outline is much less concave 
rootward than that of this face of the upper cuspid, but similarly it 
extends to a lower level lingually than labially. The lingual margin is 
well defined but the labial is rounded. 

The Distal Surface. — The convexity characteristic of this surface 
of the upper cuspid is observed here, except that the cervical portion 
is sometimes slightly concave. The surface is smaller in extent than 
the mesial, a fact due to the lower location of the distal angle. The 
cervical margin is pronounced, the surface of the root usually forming 
a decided angle with that of the crown. The lingual margin is more 
marked than the labial, but by comparison they are less clearly defined 
than those on the mesial surface. 

The Cusp. — The prominent point of the tooth occupies a line al- 
most in its long axis. From it descend the mesial and distal incisal 
edges of which the latter is slightly longer, but the difference is not so 
marked as in the upper cuspid. 

The Cervical Margin. — This is concave in the direction, of the root 
on the labial and lingual sides and convex on the mesial and distal. 
On the lingual and distal sides the root and crown join more abruptly 
than on the mesial and labial. 

The Root. — The root is shorter than that of the upper cuspid and 
is flattened on its mesial and distal sides. Viewed in profile from 
any of the four surfaces its sides slope gradually to the apex which is 
frequently inclined to the distal. 

The Pulp Cavity. — This resembles that of the upper cuspid except 
that it is narrower mesio-distally, a difference in form likewise ob- 
servable in the crowns of the two teeth. It has no horns of the pulp 
chamber but terminates in a pointed extremity beneath the cusp. 




THE UPPER FIRST BICUSPID. 1 9 

The pulp canal is flattened mesio-distally at the cervix but becomes 
circular in its apical portion. 

THE UPPER FIRST BICUSPID. 

The crown of this tooth presents for examination five surfaces, 
namely, occlusal, buccal, lingual, mesial and distal. It is irregularly 
cuboidal in shape. 

The Occlusal Surface (Fig. 29). — When viewed from the occlusal 
surface the crown appears ovoid in outline, whereas the occlusal sur- 
face proper is trapezoidal, the oval appearance being due to the pro- 
jection of the upper portion of the buccal 
face of the tooth. The most prominent 
features of this surface are the two cusps sur- 
mounting its buccal and lingual portions, the 
buccal and lingual cusps, which are separated 
by the central groove and which give to the 
tooth its distinguishing character (bicuspid). 
The margins are formed by the buccal cusp 
with its descending mesial and distal inclines, 
the mesial and distal marginal ridges, which 
are well-defined ridges of enamel joining the B ^S""^i^ , SiSS! 
ridges of the buccal cusp at the mesial and 

distal angles of the crown and converge to join descending ridges from 
the lingual cusp and the lingual cusp itself. 

The buccal cusp is the larger, sharper and more prominent. From 
its summit four ridges descend; the buccal ridge, which is partly 
responsible for the prominence of the buccal surface of the crown; 
the triangular ridge, which extends downward toward the central groove 
and usually terminates there; and one each mesially and distally to 
reach the mesial and distal angles respectively. Of these latter two, 
the distal is usually the larger and the more inclined, the point of the 
cusp being usually nearer the mesial than the distal face of the crown. 

The lingual cusp is lower and much more rounded than the buccal 
and the three ridges descending from it are less pronounced. The 
triangular ridge is often missing but when present it descends toward 
the central groove to meet the ridge from the buccal cusp. Occasion- 
ally these two triangular ridges unite and form the transverse ridge, 
but usually they are separated by a fissure in the central groove. The 
ridges descending mesially and distally from this cusp join and are 
continuous with the marginal ridges, being curved so that the lingual 
outline of the occlusal surface is much rounded. The lingual aspect 



20 THE ANATOMY OF THE HUMAN TEETH. 

of the lingual cusp is convex and rounded and gradually blends with the 
lingual surface. 

The mesio-distal groove separates the cusps and extends from the 
mesial to the distal marginal ridges. It is sometimes extended at each 
extremity into the mesial and distal developmental grooves which 
when present are fine lines crossing the marginal ridges to reach the 
mesial and distal surfaces of the crown. The triangular grooves are 
short, cross the central groove at its terminations at right angles, ex- 





Fig. 30. 



-Left Upper First Bicuspid. 
Buccal Surface. 



Fig. 31. 



-Left Upper First Bicuspid. 
Lingual Surface. 



tend toward the angles of the crown, and separate the mesial and 
distal marginal ridges from the triangular ridges. The junctions of 
these grooves with the central groove are often spoken of as the mesial 
and distal pit. 

The Buccal Surface (Fig. 30). — This closely resembles in form 
and outline the labial surface of the cuspid tooth, being smaller and 
more compressed occluso-gingivally. It is bounded by four margins, 
the occlusal, the cervical, the mesial and the distal. The occlusal is 
formed by the mesial and distal inclines of the buccal cusp and is well 
defined. The mesial incline is usually a straight line or is slightly convex. 



THE UPPER FIRST BICUSPID. 



21 



while the distal may be marked with a concavity caused by the distal buc- 
cal groove. The mesial border is more sharply defined than the distal. 
It descends from the mesial angle to the cervical border, which latter is 
nearly straight or may be slightly convex rootward and is not distinctly 
marked by an abrupt termination of the enamel. The distal margin 
is usually shorter and more rounded than the mesial, because of the 
lower position of the distal angle, and the fact that the buccal surface 
rounds into the distal without a sharp line of definition. The buccal 





Fig. 



3 2 - 



-Left Upper First Bicuspid. 
Mesial Surface. 



Fig. 



33- 



-Left Upper First Bicuspid. 
Distal Surface. 



ridge, descending from the buccal cusp and flanked by the buccal 
developmental grooves, which are forced well towards the angles of 
the crown, contributes towards the convexity of this surface. It 
usually disappears by blending with this convexity about the center 
of the surface, but occasionally in well-marked teeth it extends almost 
to the cervical margin. The greater mesio-distal diameter of the crown 
at the level of the angles than at the cervical margin gives to the crown 
its characteristic bell-shape, which may be well observed when looking 
at the buccal surface. 

The Lingual Surface (Fig. 31). — This face is smaller than the 
buccal, being both shorter and narrower. It is convex mesio-distally 



THE ANATOMY OF THE HUMAN TEETH. 

and rounds into the mesial and distal face without line of demarcation. 
Its occlusal margin is also rounded, being formed by the lingual cusp 
and the ridges descending from it, while the gingival margin is either 
ncarlv straight or is only slightly convex rootward. The surface is 
curved from the summit of the lingual cusp, which is slightly nearer 
the mesial face of the crown, to the cervix, its outline when seen in pro- 
file being a long gentle curve. It is usually quite smooth and without 



The Mesial Surface (Fig. 32). — Ir- 
regularly quadrilateral in shape, this 
face of the crown is bordered occlusally 
by the mesial marginal ridge and a 
portion of the ridge from the lingual 
cusp, and gingivally by the cervical 
line which is usually nearly straight or 
slightly concave in the direction of the 
root. The occlusal margin is concave, 
the concavity being about midway be- 
tween the cusps. Frequently this 
margin is broken by the mesial de- 
velopmental groove which reaches this 
face from the occlusal surface and 
usually terminates about its center. 
The buccal margin is fairly well de- 
fined and extends from the mesial 
angle to the cervix, while the lingual is 

Fig. 34- — Left Upper First Bicuspid. j j -l ^i j 1 • • • r 

Bucco-iingual longitudinal section, so rounded by the gradual joining of 
showing pulp chamber, its horns, and the lingual surface as to be indistin- 

the pulp canals. ° 

guishable. Near the occlusal margin 
the surface is full and rounded, giving a point of contact for the 
proximal side of the cuspid, but it flattens out as the cervix is ap- 
proached and in this location is usually the seat of a depression 
which is continued up the face of the root. 

The Distal Surface (Fig. 33). — While this is much like the mesial 
surface, it is smaller in extent and more convex. The buccal margin 
is not so pronounced as that of the mesial face and is usually shorter. 
The cervical, lingual and occlusal margins are very much like those 
of the mesial face and the lingual is poorly defined and much rounded. 
In its occlusal third the surface is quite convex in all directions and 
this usually extends in decreasing degree to the cervix, although the 
corresponding portion of the mesial face is usually concave bucco- 




THE UPPER FIRST BICUSPID. 23 

lingually. The distal developmental groove sometimes crosses the 
upper margin from the occlusal surface and disappears about the 
center of the surface. 

The Cervical Margin. — This is more nearly straight around the 
tooth than that of any of the teeth so far described, usually having, 
however, a slight curve rootward on both buccal and lingual surfaces 
and being curved toward the occlusal surface on the mesial and distal 
faces. 

The Root. — The upper first bicuspid usually has two roots (Fig. 32) 
or two branches of its root, which are located beneath its two cusps and 
are called the buccal and lingual roots. Occasionally the tooth has only 
one root, or the division may occur very near its apex. In the former 
instance the central portion of the root between 
the two pulp canals is thin and usually consists 
only of cementum. The occurrence of two 
separated roots is most frequently noted and in 
this instance the roots are delicate and taper 
gradually to a somewhat sharp apical extremity 
and are usually curved in several directions. 
These curves are usually first in a buccal and 
lingual direction, serving to separate the roots 
which again approach each other at their termi- 

rr Fig, 35.— Left Upper 

nations. There is often a gentle distal curve in First Bicuspid. Cross- 
both roots. The bifurcation is usually located ^n^^pe^f^ip 
about one-third the distance from the cervix, and canal, 
is accomplished by a meeting of the groove noted on the mesial face 
of the root and originating in the crown, with one which develops 
above the cervix on the distal side of the root. 

The Pulp Cavity. — The pulp chamber and the pulp canal are 
usually differentiated in this tooth (Fig. 34), the chamber correspond- 
ing to the general shape of the crown, the canals to the form of the 
roots. The chamber is a cavity with flattened mesial and distal walls 
and curved buccal and lingual walls. In the mature tooth these latter 
are nearly parallel and terminate occlusally in the buccal and lingual 
horns of the pulp chamber, which are cone-shaped projections of the 
cavity penetrating the two cusps. The occlusal wall of the chamber 
is marked by a projection corresponding to the central groove of the 
occlusal surface of the crown. In horizontal cross-section at this 
level, the cavity is larger than at the cervix, the mesial and distal walls 
converging to this point in correspondence with the external surface of 
the crown. 




j 4 THE ANATOMY OF THE HUMAN TEETH. 

The floor of the pulp chamber, which is usually about on a level 
with the cervix, differs in character in accordance with the root forma- 
tion of the tooth. In teeth with two roots or in those with two root 
canals, the buccal and lingual walls of the chamber are continued as 
the corresponding walls of the two pulp canals, but in old teeth a line of 
definition between the two is caused by an inward projection of the wall. 
The openings to the two canals are funnel-shaped and are separated 
by a ridge corresponding to the root bifurcation. The canals are 
usually about circular in cross-section, and follow the directions of the 
roots, occupying their centers. When the tooth has only one root, 
it sometimes has only one pulp canal (Fig. 35), which is flat and ribbon- 
like in its gingival portion, becoming more nearly round as the apex is 
reached. Often in single-rooted teeth there are two pulp canals, 
which either terminate in separate foramina close together or coalesce 
just before reaching the apex, a single canal making exit at the apex. 

THE UPPER SECOND BICUSPID. 

This tooth so closely resembles the upper first bicuspid that it will 
only be necessary to point out the differences between the two. The 
crown of the tooth is smaller and its prominences are more rounded 
than those of the first bicuspid. It is always shorter from cusps to 

cervix but the bucco-lingual diameter at 
the cervix is sometimes slightly greater than 
that of the first. On the occlusal surface 
(Fig. 36) both cusps are more rounded, 
and, unlike the first bicuspid, are usually 
of equal length. The lingual cusp is usually 
equal in size to that of the first bicuspid 
while the buccal is smaller, in consequence 
of which facts the two cusps of this tooth 
are approximately equal in size. The tri- 
■ „. , TT „ angular ridges usuallv unite to form a trans- 

FiG.36. — Right Lpper Second ° 

Bicuspid. Occlusal Surface. verse ridge, the central groove is shortened 

mesio-distally, and usually terminates in 
pits instead of well-marked triangular grooves. The buccal (Fig. 37) 
and lingual (Fig. 38) faces of the crown are smaller and more rounded 
than those of the first bicuspid, the mesial (Fig. 39) and distal (Fig. 40) 
faces being similar to those of the first except that the concavity on its 
mesial face near the cervical margin is missing. This is one of the chief 
distinguishing features of the tooth. The cervical margin more nearly 
occupies a horizontal plane than that of the first bicuspid, being 




THE UPPER SECOND BICUSPID. 



2 5 





Fig. 37. — Right Upper Second Bicuspid. Fig. 38. — Right Upper Second Bicuspid. 
Buccal Surface. Lingual Surface. 





Fig. 39. — Right Upper Second Bicuspid. Fig. 40. — Right Upper Second Bicuspid. 
Mesial Surface. Distal Surface. 



JO THE ANATOMY OF THE HUMAN TEETH. 

slightly curved rootward on buccal and lingual surfaces and being 
almost straight on the mesial and distal sides. A single root is char- 





Fig. 41. — Right Upper Second Bicuspid. Fig. 42. — Right Upper Second Bicuspid. 

Bucco-lingual longitudinal section, showing Mesio-distal longitudinal section, looking 
pulp cavity. buccally. Showing pulp cavity. 

acteristic of this tooth. It is much flattened on its mesial and distal 

sides and is usually marked with a longitudinal groove on each of 

these surfaces. Its extremity is usually rounded 

Qand occasionally bifid. Its buccal and lingual 
surfaces converge much more in reaching the 
apex than do its mesial and distal. The root 
sometimes has a curve in a distal direction near 
its termination. 
Inasmuch as this tooth normally has but one 
root, the pulp cavity consists of a pulp chamber 
corresponding in shape to that of the crown and 

a single pulp canal (Fig. 41). While the pulp 

Fig. 43--Right Upper f K F . :f" ' : . - * \ 

Second Bicuspid. Cross- chamber is similar in form to that 01 the first 

section of root above cer- bicuspid, the horns of the chamber are less 

vix, showing pulp canal. l ' 

pointed and penetrating, because of the differ- 
ences in the cusps of these two teeth. The pulp canal has its walls 
continuous with those of the chamber, no definite demarcation be- 



THE LOWER FIRST BICUSPID. 27 

tween the two existing. It is narrow mesio-distally and ribbon-like 
at the cervix but is usually easy to enter (Fig. 43). Occasionally this 
tooth has two roots, in which case two root canals can be found, and 
their existence should be considered among the rare possibilities in the 
treatment of these teeth. 



THE LOWER FIRST BICUSPID. 

While partaking of the characteristics of the upper bicuspid teeth, 
the lower first bicuspid departs from the typical bicuspid design in the 
rudimentary development of its lingual cusp. The great variation in 
the development of this cusp accounts for the variations in form so 
commonly observed in this tooth. 

The Occlusal Surface (Fig. 44). — Viewed from the occlusal surface 
the outline of the crown appears almost circular or ovoid but this is 
due to the fact that the upper portion of the bulging buccal face is 
visible. The surface presents for examination a buccal cusp, either a 
lingual cusp or a lingual ridge, a mesial and 
distal pit and marginal ridges bordering the 
surface. The summit of the buccal cusp is 
nearly in the line of the long axis of the crown. 
Four ridges descend from it, one each in a 
buccal, lingual, mesial and distal direction. 
The two latter unite at the mesial and dista 
angles with the marginal ridges. The buccal 
extends upon the buccal face of the crown and 

... . . . . . . . Fig. 44. — Left Lower First 

the lingual IS more Strongly developed, IS not Bicuspid. Occlusal Surface. 

crossed by a groove, reaches the lingual ridge 

or lingual cusp, and separates the mesial and distal pits. The mesial 
and distal marginal ridges converge to unite and form a semicircle 
with a lingual prominence of enamel, which when much elevated 
above the adjoining margin ridges is considered the lingual cusp and 
when only existing as a ridge is called the lingual marginal ridge. 

The Buccal Surface (Fig. 45). — This corresponds so closely to that 
of an upper bicuspid that detailed description would be superfluous. 
The cusp is not so pointed, the buccal developmental grooves are 
poorly developed, the crown is shorter and narrower than its fellow 
of the upper series, the cervical line is almost straight, and the surface 
is convex and slopes inward to the summit of the buccal cusp which is 
usually in line with the long axis of the root. 

The Lingual Surface (Fig. 46). — This is small because of the small 







THE ANATOMY OF THE HUMAN TEETH. 





Fig. 45. — Left Lower First Bicuspid. 
Buccal Surface. 



FiG/46.- 



-Left Lower First Bicuspid. 
Lingual Surface. 





Fig. 47- 



Left Lower First Bicuspid. 
Mesial Surface. 



Fig. 48.- 



-Left Lower First Bicuspid. 
Distal Surface. 



THE LOWER FIRST BICUSPID. 



20 



size and low position of the lingual cusp. The occlusal margin is well 
defined and the surface is nearly straight from this point to the cervix 
and in many instances is continued without marked division into the 
surface of the root or it may make an obtuse angle with this face of the 
root. Mesio-distally it is much rounded passing into the proximal 
surfaces with a gentle curve. 

The Mesial Surface (Fig. 47). — Irregularly quadrilateral in out- 
line, with only its occlusal margin well defined by the marginal ridge, 








A 
















\ 






1 




•> 


v.-; 





Fig. 49. — Right Lower First Bicuspid. 
Mesio-distal longitudinal section, showing 
pulp cavity. 



Fig. 50. — Right Lower First Bicuspid. 
Bucco-lingual longitudinal section, show- 
ing pulp cavity. 



this surface is generally convex. The most prominent point of the 
convexity is located centrally just below the occlusal margin from which 
the surface inclines inward toward the central axis of the tooth, con- 
tributing thereby to give the bell-shape which is observed of this crown 
as it is viewed from the buccal or lingual side. At the cervix the surface 
is flattened. 

The Distal Surface (Fig. 48). — This is almost similar to the mesial 
except that its convexity is usually less pronounced. 

The Cervical Margin. — The juncture between enamel and cemen- 
tum in this tooth occupies nearly a horizontal plane, being continued 




$0 THE ANATOMY OF THE HUMAN TEETH. 

around the tooth in almost a straight line. There is frequently a dip 
rootward on the buccal face. 

The Root. — A single root normally characterizes the lower 
first bicuspid although in rare instances two roots are found. When 
single it is conical, the buccal and lingual sides being uniformly in- 
clined toward each other and continuing these faces of the crown. 
The lingual is the narrower, which is caused by the fact that the flat- 
tened mesial and distal faces converge in passing 
lingually. These latter are usually slightly con- 
vex and uniformly taper to the apex, but occa- 
sionally they are marked with a shallow longit- 
udinal depression. The end of the root is 
sharply pointed and is frequently deflected dis- 
tally. The cervical portion of the root is oval 
in cross-section. 
^. FlG -5 I - Ri | ht Lower The Pul p Cavity.— As in all single rooted 

First Bicuspid. Cross- * y ° 

section at cervix showing teeth there is no sharp division between the 
pu p cana . pulp chamber and canal (Fig. 49) . The cham- 

ber has one well-defined horn situated beneath the buccal cusp and 
when a lingual cusp exists there is a small projection of the cavity in 
its direction (Fig. 50). At the level of the gingival margin the 
cavity is oval in cross-section whence it continues diminishing in bucco- 
lingual diameter to the apical foramen (Fig. 51). It is usually small 
and thread-like in the apical third of the root. 

THE LOWER SECOND BICUSPID. 

While this tooth bears a close resemblance to the lower first bicus- 
pid tooth in many particulars, in some details it is quite different. 
These chiefly pertain to the lingual portion of the occlusal face of the 
crown and the adjacent surfaces which are related therewith. In 
general the crown of the tooth is smaller and more rounded than 
the first. Viewed from the occlusal face it will be seen that this 
surface is larger and even more nearly circular in outline than the 
first. In some instances this is due to the presence of a well-developed 
lingual cusp and prominent marginal ridges mesially and distally. 
In other instances the same rounded outline is caused by the presence 
of two lingual cusps, a fissure dividing the lingual portion in its center. 
The buccal cusp is less prominent than that of the first bicuspid, and 
has a well-defined triangular ridge which seldom unites with that of 
the lingual cusp. When present the lingual cusp is smaller than and 



THE UPPER FIRST MOLAR. 3 1 

not so prominent as the buccal and is usually separated from it by a 
mesio-distal groove. This latter terminates in pits, the mesial and 
distal pits, and is curved lingually. When the face presents three 
cusps the groove has three branches meeting in a contral pit or fossa. 
The angles of the crown are not well marked. 

The buccal surface is more rounded and shorter and wider than that 
of the first bicuspid. The lingual surface is proportionally larger than 
the lingual of the lower first bicuspid, being longer occluso-gingivally 
because of the lingual cusp at the base of which it is also wider 
mesio-distally. The mesial and distal faces of the crown are 
similar to those of the first bicuspid except that they are wider bucco- 
lingually and are both slightly more convex. The cervical margin 
encircles the tooth almost in a horizontal plane, but a curve rootward 
may usually.be made out on the buccal face. The single root is con- 
ical, proportionately longer than that of the first bicuspid, flattened on 
its mesial and distal sides, and usually bent distally in its lower portion. 
The pulp cavity is larger than that of the first bicuspid, the chamber 
being shaped to correspond with the external surface of the crown and 
having the rudimentary lingual horn better developed. The canal is 
oval or circular in cross-section at the cervix from whence it tapers 
gradually to the apical foramen. 

THE UPPER FIRST MOLAR. 

The crown of the upper first molar is roughly cuboidal in shape and 
offers for examination five surfaces — occlusal, buccal, lingual, mesial 
and distal. 

The Occlusal Surface (Fig. 52). — This is irregularly rhomboidal in 
outline as may be seen when the crown is viewed from this surface. 
The mesial and distal margins are nearly straight and parallel; the 
buccal and lingual margins are curved. At the mesio-buccal and 
disto-lingual juncture of these margins acute angles are formed while 
the angles at the disto-buccal and mesio-lingual juncture are obtuse. 
The surface is marked by the presence of four cusps, four marginal 
ridges, two fossae, and several developmental grooves. The mesial 
marginal ridge is a rounded and well-defined elevation of enamel 
extending from the summit of the mesio-buccal cusp to that of the mesio- 
lingual cusp, and is curved rootward between these points. It is often 
crossed near its center by the mesial developmental groove which ex- 
tends from the occlusal to the mesial surface. The buccal marginal 
ridge unites with the mesial at the mesio-buccal angle of the tooth. It 



3a 



THE ANATOMY OF THE HUMAN TEETH. 



extends from this point to the point of the mesio-buccal cusp, then 
in a slightly lingual direction to the bottom of the buccal groove, then 
buccally to the point of the disto-buccal cusp and then to the disto- 
buccal angle, being curved latterly in a lingual direction to unite with 
the distal marginal ridge. It is the sharpest of the marginal ridges, 
a fact in large part due to the sharpness of the buccal cusps. 

The distal marginal ridge is similar to the mesial in that it is curved 
rootward between its terminations and is a rounded ridge of enamel. 
It is marked to the buccal side of its center by the distal groove, which 
passes over upon the distal face of the crown. The lingual termina- 
tion is well rounded and consequently 
less easily differentiated from the disto- 
lingual cusp in which it terminates. The 
lingual marginal ridge completes the 
periphery of the occlusal surface, ex- 
tending from the disto-lingual to the 
mesio-lingual angle of the crown. From 
its mesial end it curves lingually to the 
summit of the mesio-lingual cusp, then 
buccally to the point where it is divided 
by the disto-lingual cusp and then 
lingually again to the top of the disto- 
lingual cusp. It is the most rounded 
of the marginal ridges. 

The Cusps. — The upper first molar 
may be said to possess four cusps nor- 
mally but in a large number of cases it has five. The mesio-buccal 
cusp, located near the mesio-buccal angle of the tooth, is sharp and 
from its summit descend four ridges. These latter are the buccal, 
which continues upon the buccal surface of the crown, the triangular 
which descends into the central fossa, and the two ridges descending 
mesially and distally forming portions of the buccal marginal ridge. 
The disto-buccal cusp is somewhat smaller than the one just described, 
but like it is sharp and has four ridges descending from its point. The 
buccal ridge descends upon the buccal face, the mesial and distal 
ridges are portions of the buccal marginal, while the fourth ridge unites 
with one from the mesio-lingual cusp to form the oblique ridge. The 
disto-lingual cusp is usually the smallest (except the fifth) and is 
rounded. But two ridges descend from it, one each in a mesial and 
lingual direction to form the marginal ridge of these boundaries. Its 
lingual and distal aspects fade off into these respective faces of the 




Fig. 52. — Left Upper First Molar 
Occlusal Surface. 



THE UPPER FIRST MOLAR. 

crown without demarcation. It is separated from the oblique ridge 
by the disto-lingual groove. The mesio-lingual cusp is frequently 
the largest cusp of this tooth. It is much rounded and has ridges 
descending from it as follows : one to the mesial to join the mesial mar- 
ginal ridge and one distally forming a portion of the lingual marginal 
ridge, w T hile one passes in the direction of the disto-buccal cusp, meet- 
ing a ridge from the latter to form the oblique ridge. The buccal 





Fig. 53. 



-Left Upper First Molar. 
Buccal Surface. 



Fig. 54. — Left Upper First Molar. 
Lingual Surface. 



aspect of the cusp forms a wall of the central fossa, while the lingual 
side is rounded and descends without demarcation into the lingual 
surface of the crown, or in teeth with a fifth cusp descends into the 
groove dividing the latter from the crown. The fifth cusp, or lingual 
cingule as it is sometimes called, varies much in size and occurrence. 
When present it is an elevation of enamel on the lingual surface of the 
crown, near and just distal to the mesio-lingual angle and at the lingual 
base of the mesio-lingual cusp from which it is separated by a groove, 
the mesio-lingual. 

The Fossce and Grooves. — The central fossa is triangular in shape 
and occupies the space between the mesio-buccal, disto-buccal and 
mesio-lingual cusps, its walls being formed by the central inclines of 
3 



34 



THE ANATOMY OF THE HUMAN TEETH. 



these cusps and the mesial marginal ridge. In its center is the central 
pit from which radiate the mesial developmental groove, which passes 
forward over the mesial marginal ridge to the mesial face of the crown, 
the buccal groove which divides the mesio-buccal from the disto-buccal 
cusp and reaches the buccal surface of the crown, and the distal which 
is less well marked and passes distally over the oblique ridge. Each 
of these grooves may be the seat of a fault or fissure, the buccal 
exhibiting it more commonly and the distal less commonly than the 

others. The distal fossa is 
smaller than the central and 
is located between the disto- 
lingual and disto-buccal cusps 
and «the distal marginal and 
oblique ridges. Its longest di- 
mension is disto-lingually in 
which direction it is traversed 
by the disto-lingual groove. 
This latter has its terminations 
in the lingual pit near the cen- 
ter of the lingual surface and 
a pit in the distal fossa. It is 
parallel to the oblique ridge, 
dividing the disto-lingual cusp 
from this, and is usually the 
seat of a fissure, the result of 
faulty union of the develop- 
mental lobes of the crown. 
The distal groove passes 
through this fossa, crossing the 
oblique ridge anteriorly and the distal marginal ridge posteriorly. 

The Buccal Surface (Fig. 53). — This is bounded by four margins, 
of which the occlusal is irregular, sharp and prominent, being formed 
by the buccal marginal ridge and the two buccal cusps, the cervical is. 
almost straight, while the mesial and distal are not well marked, the 
distal being less so than the mesial. The two latter are rounded 
and fade into the respective faces of the crown. They converge from 
the occlusal surface to the cervix, so that when the tooth is viewed 
from the buccal face the bell-shape of its crown is noticeable. For 
the most part the surface is slightly convex having, however, a depres- 
sion near its center in which is frequently located a buccal pit. The 
buccal groove divides it into two lobes and usually terminates in the 




Fig. 55. 



-Left Upper First Molar. 
Mesial Surface. 






THE UPPER FIRST MOLAR. 



35 



buccal pit, but the depression is sometimes continued rootward and is 
continuous with that between the two buccal roots. At the cervix 
there is a ridge of enamel, the cervical ridge, which gives prominence 
to this line. 

The Lingual Surface (Fig. 54). — This is somewhat similar in out- 
line to the buccal, but is narrowed mesio-distally at the cervix as the 
sides converge to a single root instead of two as upon the buccal surface. 
The surface is more convex than the buccal, but, like it, is often the 
seat of a pit near its center, the 
lingual pit, in which the disto- 
lingual groove terminates. The 
depression caused by this groove 
is often continued rootward, 
dividing the surface into two 
lobes, and being continuous 
with a longitudinal depression 
upon the lingual root. The 
distal lobe is rounded in every 
direction, its distal portion be- 
ing continuous with the distal 
face of the crown without de- 
marcation. The mesial lobe 
resembles this in character ex- 
cept that its anterior margin is 
more defined. In those teeth 
with five cusps this lobe pre- 
sents near the occlusal margin 
a rounded cingule, whose lin- 
gual side is continuous with 

the lingual face of the crown, but which is separated from the mesio- 
lingual cusp by a groove, the mesio-lingual groove. This latter 
often terminates distally by uniting with the disto-lingual groove, but 
frequently at each extremity it fades away into the surface of the 
tooth. The cervical line is almost straight, the mesial and distal 
margins are curved and converge toward the cervix, while the occlusal 
margin resembles that of the buccal face except that the cusp points 
are not so sharp and the marginal ridge is more rounded. 

The Mesial Surface (Fig. 55). — While this is generally convex 
bucco-lingually near the occlusal margin, in its gingival two-thirds 
it is either flat or it may be slightly concave. It is either convex 
or nearly flat occluso-gingivally, and the most prominent point is 




Fig. q6. 



-Left Upper First Molar. 
Distal Surface. 






j<5 THE ANATOMY OF THE HUMAN TEETH. 

slightly above the occlusal margin where the tooth is in contact with 
the second bicuspid. The surface is bounded by four margins— 
the cervical is usually concave in an occlusal direction, while the 
occlusal is concave in a cervical direction because of the mesial groove 
which is sometimes continued for a short distance upon this surface. 
The buccal and lingual margins are convex and converge to the occlusal 
surface. They are rounded, the former being better defined than the 
latter. The lingual margin is modified by the presence or absence of 
the lingual cingule, the location of the notch caused by the mesio- 
lingual groove varying according to the height of the cingule. 

The Distal Surface (Fig. 56). — Four 

sided, this surface resembles the mesial 
in general outline. It is generally con- 
% vex, except that often the distal groove 
^^| % is continued and makes a slight longit- 

"' v H K udinal depression near its center. The 

occlusal margin is more deeply notched 
than that of the mesial surface, the cer- 
vical line is nearly straight or concave 
Mj| occlusally while the buccal and lingual 

fchttiu m ijlr l margins are rounded, the former being 

^SgltllSfpf ' less well defined than the latter. 

'^hBK^ The Roots (Figs. 53 and 54).— These 

I are three in number and are named from 
their location, the mesio-buccal, disto- 

Fig. 57. — Right Upper First Molor. . , . .. . _. , 

Cross-section below cervix, showing buccal and lingual. They are not given 
the pulp chamber and entrances to off directly from the base of the crown, 

the pulp canals. J 

but the division which results in them 
occurs usually about one-third the distance from the cervix to the 
root apices. 

The mesio-buccal root (Fig. 55) is flattened antero-posteriorly, 
and is next to the lingual in size and length. Viewed from its mesial 
side, it is nearly equal in width to half the crown and its sides slowly 
converge to near its end when they meet in a blunt, rounded point. 
From this view the root is inclined buccally, while viewed from the 
buccal side, it is seen to have a mesial inclination in its first third, 
curving then in a distal direction to its extremity. It is thin and flat 
mesio-distally. 

The disto-buccal root (Fig. 56) is the smallest. It is narrower 
bucco-lingually than the mesio-buccal and is short. Its sides gradually 
incline to a more or less pointed apex, and it is slightly flattened mesio- 



THE UPPER FIRST MOLAR. 



37 



distally. In its first third it is inclined distally, but in the remainder 
of its extent it is usually inclined mesially, approaching the mesio- 
buccal root. 

The lingual root (Fig. 54) is the largest and usually the longest of 
the three roots. It is somewhat flattened bucco-lingually, and it is 
either nearly straight or slightly curved, in which latter instance its 
extremity is inclined buccally. It diverges markedly from the buccal 
roots in a lingual direction. ' Viewed from the lingual face the sides 
of the root are markedly convergent, 
sloping from the base of the crown 
to a somewhat rounded apex. 
This face of the root often pre- 
sents a longitudinal depression 
which is continuous with that on 
the lingual side of the crown. 

The Pulp Cavity (Fig. 57). — 
The pulp cavity is easily separable 
into the pulp chamber and the pulp 
canals, of which the former is ap- 
proximately the shape of the exterior 
of the crown of the tooth, while the 
latter, which are three in number, 
correspond to the general external 
shape of the roots. The pulp 
chamber is characterized by four 
horns or depressions in its occlusal 
wall, one entering each of the four 
cusps. Its four lateral walls are 
parallel to the sides of the crown 
and are generally flat. In bell- 
shaped teeth they converge from 

the occlusal wall to the floor (Fig. 58) which is much smaller than the 
occlusal wall, while in teeth whose crown walls are nearly parallel 
without constriction at the neck, the lateral pulp chamber walls are 
similarly disposed. 

The horns of the pulp chamber are marked and penetrating and 
often persist in mature teeth as deep recesses in the dentin. The floor 
of the pulp chamber presents the three openings for the pulp canals. 
In the young adult tooth these are in the form of funnel-shaped open- 
ings. As age increases, the size of the pulp chamber decreases. The 
thickening of the lateral walls encroaches upon the pulp chamber, the 




Fig. 58. — Right Upper First Molar. 
Longitudinal section cut through the pulp 
canals of the buccal roots, showing the 
pulp chamber and its horns. 



3« 



THE ANATOMY OF THE HUMAN TEETH- 



funnel-like openings to the canals become simply small apertures and 
the canals are much reduced in size. 

The lingual canal (Fig. 57) is the largest and most accessible. It 
does not conform to the flattened shape of the root but is usually cir- 
cular, decreasing gradually in caliber to the apex, and following 
the curvature of the root already noted. The entrance to it is directly 
under the middle of a line drawn from the summit of one lingual cusp 
to the other. The mesio-buccal canal (Fig. 58) is next in size and 
length. The entrance to it is very near the mesio-buccal angle of the 
tooth, slightly anterior to the summit of. the mesio-buccal cusp. It 
is flat and ribbon-like and follows the curvature of the root. The disto- 
buccal canal (Fig. 58) is small and thread-like. Its entrance is approx- 
imately under the disto-buccal cusp. It is short and difficult to enter. 

THE UPPER SECOND MOLAR. 



The crown of this tooth differs from the first molar in any given 
denture in that it is flattened mesio-distally, with a rounding of the 
mesio-lingual and disto-buccal angles; its cusps are not so long and 
their summits are nearer the center of the tooth; it almost never pos- 
sesses a fifth cusp or cingule, and the 
disto-lingual cusp is relatively smaller 
than that of the first molar. 

The Occlusal Surface (Fig. 59). — 
When the crown is viewed from the 
occlusal surface this latter is seen to be 
rhomboidal in outline but with the angles 
more rounded than those of the first 
molar and with the lingual margin almost 
semicircular. The mesial marginal, the 
distal marginal, the buccal and the 
lingual marginal ridges are formed as 
they are in the first molar. In this tooth 
they are more rounded. The mesio- 
buccal cusp has four ridges descending 
from its summit, one each in a buccal, lingual, mesial and distal direc- 
tion. It is smaller and less sharp than the corresponding cusp of the 
first molar. The disto-buccal cusp is usually small and pressed in 
toward the center of the crown by the rounding of the disto-buccal angle. 
Its buccal ridge is absent or barely distinguishable. The mesio-lingaul 
cusp is usually the largest cusp and is well rounded and without a clearly 




Fig. 59. — Left Upper Second 
Molar. Occlusal Surface. 



THE UPPER SECOND MOLAR. 



39 



defined point. It has ridges which pass mesially, distally and buccally, 
the latter is heavy and strong and assists in forming the oblique ridge. 
The lingual surface of the cusp is much rounded. The disto-lingual 
cusp varies much in size and form. It is usually relatively smaller 
than that of the first molar. Often it is little more than an enlarge- 
ment of the distal marginal ridge, with which its buccal ridge is contin- 
uous. Its distal and lingual faces are much rounded. The central 
fossa is not so deep as that of the first molar, though similarly its walls 
are formed by the two buccal cusps and the mesio-lingual together with 





Fig. 60.- 



-Left Upper Second Molar. 
Buccal Surface. 



Fig. 6i. — Left Upper Second Molar. 
Lingual Surface. 



the mesial marginal and oblique ridges. The mesial groove, the buccal 
groove and the distal groove all pass from it in these respective directions. 
It has a pit, the central pit, in its center, and the distal fossa has, simi- 
larly, the distal pit. From the latter fossa the distal groove passes to 
the distal surface and the disto-lingual to the lingual surface, ending 
on the latter usually in the lingual pit. 

The Buccal Surface (Fig. 60). — This resembles that of the first 
molar so closely that only their points of difference need to be pointed 
out. The occlusal margin has the same outline as that of the first 



40 



THE ANATOMY OF THE HUMAN TEETH. 




molar except that the smaller 
proportionate size of the disto- 
buccal cusp causes this portion 
to be slightly altered. The distal 
margin is more rounded and less 
pronounced than that of the first 
molar, but the other two margins 
are similar. The buccal groove 
continues upon the buccal face, 
from the occlusal surface, some- 
times to the point of bifurcation 
of the roots, less rarely ending in 
a buccal pit. The lobe of the 
crown mesial to the depression 
is always larger than the distal 
lobe. The cervical ridge is not 
so frequently marked. 

The Lingual Surface (Fig. 
61). — This differs in no wise 



Fig. 62. — Left Upper Second Molar. 
Mesial Surface. 



from that of the first molar ex- 
cept that it is much more con- 
vex and the fifth cusp is almost 
never present to modify the form 
of its mesial portion. 

The Mesial Surface (Fig. 62). 
— This resembles closely the cor- 
responding surface of the upper 
first molar, but is relatively 
smaller and is often concave 
from buccal to lingual side. Its 
lingual margin is less well de- 
fined than its mesial. 

The Distal Surface (Fig. 63). 
— Usually more convex than this 
surface of the first molar, and 
relatively shorter occluso-gingi- 
vally, the distal surface of this 
tooth resembles in other respects 




Fig 



63. — Left Upper Second Molar. 
Distal Surface. 



THE UPPER THIRD MOLAR. 



41 




Fig. 64. — Right Upper Second 
Molar. Cross-section at cervix 
showing pulp chamber. 



its mesial neighbor. The varying size and portion of the disto-lingual 

cusp influence the exact form of this face 

of the crown. 

The Roots. — Alike in number and gen- 
eral form to those of the first molar, the 

roots of the second differ in some respects 

from them. The mesio-buccal (Fig. 62) 

is flattened antero-posteriorly, the disto- 

buccal (Fig. 63) is nearly conical, while the 

lingual root (Fig. 61) is longest, largest and 

flattened bucco-lingually but seldom ex- 
hibits the depression observed on this root 

of the first molar. The two buccal roots 

have a distinct distal inclination and tend 

to converge at their apices. The disto- 

buccal root occupies a position relatively 

more lingual than that of the first 
molar because of the flattening of 
the disto-buccal angle of the crown. 
The Pulp Cavity. — The differ- 
ences between the form of this and 
that of the first molar correspond 
to the differences in the surface 
forms of the two teeth. 

The pulp chamber is flattened 
mesio-distally (Fig. 64) and the 
entrances to the canals are rela- 
tively nearer together and that of 
the disto-buccal canal is more 
lingually located. The horns of 
the pulp chamber are four in 
number but are smaller and less 
penetrating than those of the first 
molar. The root canals have the 
same shape as those of the first 
molar but are smaller and more 
difficult to enter (Fig. 65). 




Fig. 65.— Right Upper Second Molar. 
Longitudinal Section cut through mesio- 
buccal root canal, showing pulp chamber. 



THE UPPER THIRD MOLAR. 

Greater variation occurs in the form of this tooth than in that of 
any other in the dental series. In its typical form it has only three 



4- 



THE ANATOMY OF THE HUMAN TEETH. 



cusps, the disto-lingual cusp having disappeared, while in its most 
strongly developed form this is present but is much reduced in size 
by comparison with the other cusps of the tooth. Many atypical 
teeth are observed in which the cusp development is difficult to classify. 
A description will be given of the typical tooth. 

The Occlusal Surface (Fig. 66). — This is marked by the presence of 
a mesio-buccal, a dieto-buccal and a mesio-lingual cusp. The disto- 
lingual is represented only in the distal marginal ridge, or may be en- 
tirely absent when the oblique ridge forms the posterior margin of the 
surface. The buccal cusps are like in form to those of the first and 
second molars except that they are shorter and smaller. The mesio- 





Fig. 66.— Left Upper Third Molar. 
Occlusal Surface. 



Fig. 67.- 



-Left Upper Third Molar. 
Buccal Surface. 



lingual cusp is large and rounded and the central fossa is well defined; 
usually many small ridges descend from the cusps into it. The mesial 
marginal ridge is well defined, the buccal depends in character upon 
the buccal cusps and the lingual is usually poorly discernible. The 
posterior margin may be either formed by the triangular ridge or the 
distal marginal ridge may be present. 

The Buccal Surface (Fig. 67). — In typical teeth this resembles the 
buccal face of the second molar but is smaller in extent, more rounded, 
and its distal lobe is poorly defined. 

The Lingual Surface (Fig. 68). — Variations in the form of this 
surface are caused by the presence or absence of the disto-lingual cusp 
— when present, this cusp surmounts a lobe of this surface which is 
partially divided from the mesial lobe by the disto-lingual groove. 
In this event the mesial lobe resembles that of the second molar but 



THE UPPER THIRD MOLAR. 



43 



is even more convex. When the lingual side is surmounted only by 
one cusp, it is much rounded and convex and joins the mesial and distal 
faces almost without line of demarcation. 

The Mesial Surface (Fig. 69). — This resembles that of the second 
molar in being flat and sometimes concave from buccal to lingual 
sides, but it is smaller in extent of surface. 

The Distal Surface (Fig. 70). — While it is usually rounded from 
buccal to lingual side, being always so when the disto-lingual cusp is 
absent, this surface may also be flat or even concave, when the crown 
has four cusps. It is always smaller in area than the mesial surface or 
than the distal surface of the first and second molars. 





Fig. 68.— Left Upper Third Molar. 
Lingual Surface. 



Fig. 69. 



-Left Upper Third Molar. 
Mesial Surface. 



The Roots. — These vary much even in teeth which are typical in 
regard to thier crowns. There are sometimes three roots, a mesio- 
buccal, a disto-buccal and a lingual, w T hich are usually short and have 
a distal and a lingual curvature. These are sometimes fused together 
throughout most of their length. Occasionally only one root is seen 
caused by the complete fusion of the roots. Occasionally also four 
roots may be found (Fig. 71). 

The Pulp Cavity. — The external form of the crown largely deter- 
mines the form of the pulp cavity, so that in trituberculate teeth this 
cavity is triangular in cross-section w T hile in quadrituberculate teeth, 
it has the general form of the pulp chamber of the other upper, molars. 
Its lateral walls converge more to the floor of the pulp chamber which 
is situated at a higher level than that of the pulp chamber of the second 
molar. The horns of the pulp chamber are less well defined and are 



44 



THE ANATOMY OF THE HUMAN TEETH. 



shorter than those of the other upper molars and correspond in number 
to the number of cusps in any given tooth. The pulp canals usually 
correspond in number with the number of roots except that in teeth 
in which the roots have fused into a single one, there may be three or 
even four root canals, which sometimes have separate apical fora- 
mina, or again may unite before this is reached and have a common 





Fig. 70. — Left Upper Third Molar. 
Distal Surface. 



Fig. 71. — Left Upper Third Molar. 
With roots not completely developed 
and atypical in having four roots. 
Showing large patulous openings into 
root canals. 



termination. Occasionally in the single rooted tooth there is only 
one large canal, the walls of which are continuous with those of the 
pulp chamber and converge to a small foramen at the root apex. 
Where more than one canal exists, they are small and thread-like, 
quite short as the roots are short, and the openings from the pulp 
chamber into them are very close together. 



THE LOWER FIRST MOLAR. 

The largest tooth of the human series is the lower first molar, which 
is longer mesio-distally than the upper first molar, and is of about 
equal width. The five surfaces of its crown may be described. 

The Occlusal Surface (Fig. 72). — This is irregularly trapezoidal 
in outline, its four margins usually being rounded. The buccal and 
lingual are more convex than the mesial and distal which may be al- 
most straight. These latter converge toward the lingual side in 
consequence of which this is shorter than the buccal. Five cusps are 
usually present, three upon the buccal side and two upon the lingual. 
A central fossa is formed and occupies nearly the center of the surface 
and from this radiate grooves separating the cusps. Four ridges 



THE LOWER FIRST MOLAR. 45 

bound the surface. The mesial marginal ridge is the best defined of 
these. It passes from the mesio-buccal to the mesio-lingual angle of 
the crown, is concave rootward and is usually crossed near its center 
by the mesial groove. It is continuous at its buccal and lingual ex- 
tremities with the marginal ridges of these names. The buccal marginal 
ridge is poorly defined, is bowed in a buccal direction, and is made up of 
the ridges descending mesially and distally from the three buccal cusps. 
The distal marginal ridge is not so prominent as the mesial but is like 
it in other respects. It is commonly crossed by the distal groove. 
The lingual marginal ridge is made up of the ridges descending ante- 
riorly and posteriorly from the two lingual cusps. It is cut near its 
center by the lingual groove and 
is somewhat sharper than the 
buccal marginal ridge. 

The mesio-buccal cusp is 
usually the largest and some- 
times the longest cusp of this 
tooth. It is a rounded elevation 
with ridges descending mesially, 
buccally, and distally, and some- 
times two or more toward the 
central fossa from its lingual 

Sides. The names of these Fig. 72.-RJ.ght Lower First Molar. 

Occlusal Surface. 

ridges correspond to the direc- 
tion in which they descend from the point of the cusp, except that the 
lingual ridge is usually spoken of as the triangular. It is the most 
sharply defined of all. 

The buccal cusp is next in size of the buccal series of cusps, being 
intermediate in size and position between the mesio-buccal and the 
disto-buccal cusp. It has also four ridges which pass in a buccal, 
lingual, mesial and distal direction respectively. The lingual ridge 
descends into the central fossa and is called the triangular ridge. 
The disto-buccal cusp is separated from the last described cusp by 
the disto-buccal groove. It varies in size and position. It is more 
prominent buccally where it is of greatest size, but when found of 
small size it is located nearer the distal face of the tooth and there is 
a corresponding increase in the size of the buccal cusp. 

The disto-buccal is always the smallest cusp. Three ridges, a 
mesial, a distal and a triangular, may usually be observed, but its 
buccal surface is rounded and convex. 

The lingual cusps are sharper than the buccal cusps. The mesio- 




46 



THE ANATOMY OF THE HUMAN TEETH. 



lingual is sharp and prominent in the unworn tooth and its summit 
is near the mesio-lingual angle. Its lingual surface is continuous 
with that of the crown but ridges descend mesially, distally, and 
buccallv. The triangular ridge passes into the central fossa and ter- 
minates at the mesial groove opposite the triangluar ridge from the 
mesio-buccal cusp. These two ridges are separated from the mesial 
marginal ridge by a shallow depression running bucco-lingually. 
The disto-lingual cusp is usually smaller than the mesio-lingual, 





Fig. 73. — Right Lower First Molar. 
Buccal Surface. 



Fig. 74. — Right Lower First Molar. 
Lingual Surface. 



but like it, is pointed and has three ridges descending from its summit, 
and otherwise resembles it in shape. 

The central fossa occupies approximately the center of the occlusal 
surface, and is broad and shallow. The mesial and distal marginal 
ridges and the five cusps contribute to form its walls. The mesial 
groove passes from it to the mesial surface, the buccal groove is well 
marked, usually the seat of a fissure, and passes buccallv between the 
mesio-buccal and buccal cusps; the disto-buccal groove, also frequently 
the seat of a fissure, passes between the buccal and disto-buccal cusps; 
the distal groove crosses the disto-marginal ridge and the lingual groove 






THE LOWER FIRST MOLAR. 



47 



passes between the lingual cusps, although in some instances it is very 
poorly marked. The floor of the central fossa is flat and frequently 
small tubercles of enamel are found divided from each other by fine 
grooves. The central pit, a fault in the enamel, is usually found 
where the buccal and lingual grooves meet and a distal pit often at the 
occlusal termination of the disto-buccal groove. 

The Buccal Surface (Fig. 73). — This is trapezoidal in shape, and is 
convex mesio-distally and occluso-gingivally. The mesial and distal 





Fig. 75. 



-Right Lower First Molar. 
Mesial Surface. 



Fig. 76. 



-Right Lower First Molar. 
Distal Surface. 



margins are much rounded and ill defined, the occlusal margin is 
marked by three elevations, the cusps, and two grooves, and the cer- 
vical is usually convex rootward and marked with a prominent ridge 
of enamel, the cervical ridge. The buccal groove crosses the surface 
a little mesial to its center and, decreasing in depth, is continuous with 
the depression caused by the bifurcation of the roots, or it terminates 
half way between the occlusal and cervical margin in a well-defined de- 
pression, the buccal pit. 

The disto-lingual groove is less deep at the occlusal margin and 



48 



THE ANATOMY OF THE HUMAN TEETH. 



terminates by disappearing about half way from the cervix. These 
grooves divide the buccal surface into lobes of which the mesial is 
most strongly marked, the central and distal being more rounded and 
usually uniting at the cervical portion, being separated at their occlusal 
portion by the disto-buccal groove. 

The Lingual Surface (Fig. 74). — This is convex in all directions 
but is less so occluso-gingivally than the buccal because of the sharp- 
ness of the lingual cusps. Its mesial and distal margins are much 
rounded and converge to the cervical which is convex rootward. The 
occlusal margin is marked by the two cusps and the lingual groove. 
The latter is often poorly marked although it is occasionally deep, but 

usually disappears about the center 
of the surface, and the division of 
this surface by it into two lobes is 
not usually distinct. 

The Mesial Surface (Fig. 75). — 
While it is generally convex and 
usually so near the occlusal margin 
where it affords a point of contact 
with the second bicuspid, this sur- 
face is sometimes flat and usually 
a concavity may be noted near the 

Fig. 77. — Right Lower First Molar. . ' 

Cross-section at cervix, showing the cervical line. The occlusal margin 
^1?^^ ^ entrances to the pulp is notched by the mesial groove 

between the two mesial cusps, the 
lateral margins are rounded and convex in an occlusal direction. 

The Distal Surface (Fig. 76). — This resembles the mesial face of 
the crown in outline, but is more convex. Its cervical and lingual 
margins are like those of the mesial but the varying size and position 
of the disto-buccal cusp determine the occlusal and buccal margins. 
The latter is rounded and the former is marked by the distal groove. 
These unite at the disto-buccal cusp, the position of which determines 
whether the occlusal margin is long or short. 

The Roots. — There are two roots (Fig. 73), named from their posi- 
tions, mesial and distal. They are both broad and much flattened 
mesio-distally. The point of bifurcation is about one-fourth the dis- 
tance from the cervix to the root apices. The mesial root when viewed 
from the mesial surface (Fig. 75) is seen to be flat, its sides converging 
but slightly to a blunt apex. On both its mesial and distal surfaces 
a longitudinal depression running the length of the root may be ob- 
served. The mesial and distal sides are nearly parallel until the apex 







THE LOWER SECOND MOLAR. 



49 



is reached. The root is curved mesially so that its lower third has a 
decided distal turn. The distal root is usually straight and is flattened 
also mesio-distally. It is not marked by longitudinal depressions on 
its mesial and distal sides, terminates in a sharper apex than the 
mesial root, and is not so long. 

The Pulp Cavity.— The chamber corresponds in general to the 
shape of the crown, being quad- 
rilateral in horizontal cross- 
section (Fig. 77). The occlusal 
wall of the chamber in young 
teeth has five horns which are 
in relation with the five cusps, 
but these are very poorly marked 
because of the shortness of the 
cusps. The lateral walls are 
four in number, the buccal wall 
being of greatest extent. These 
converge to the floor (Fig. 77) 
which is concave bucco-lin- 
gually and convex mesio-distally. 
The buccal and lingual walls 
meet in a trough- like depres- 
sion which dips down anteriorly 
and posteriorly to the entrance 
into the pulp canals. In any 
but old teeth the mesial and 
distal walls (Fig. 78) are contin- 
uous with the walls of the pulp 
canals. The openings to the 
latter are funnel-like. There 
are usually two canals in the mesial root which are fine and thread- 
like and round. They occasionally meet before the apex of the root is 
reached and terminate in a common foramen although they usually 
make exit by separate foramina. The distal pulp canal is larger and 
ovoid in cross- section and easily entered. 




Fig. 78. — Left Lower First Molar. Mesio- 
distal longitudinal section cut through the 
buccal cusps and the pulp canals, showing 
pulp chamber and canals. 



THE LOWER SECOND MOLAR. 

The crown of the lower second molar differs from that of the first 
in that it has four cusps of nearly equal size instead of five. In other 
particulars its surface form is very similar. 

The Occlusal Surface (Fig. 79). — The occlusal surface presents 



50 THE ANATOMY OF THE HUMAN TEETH. 

for examination four cusps of nearly equal size, situated near its four 
angles. The summits of the cusps are nearer the center of the crown 
than are those of the first molar and are more rounded. The out- 
line of this surface is more rounded than that of the first molar, the 
mesial and distal margins being of equal length and convex. The 
buccal and lingual are also usually of equal length but in some instances 
that of the former is greater. The mesial and distal marginal ridges 
are similar to those of the first molar, and the surface has a central 
fossa from which a mesial, distal, buccal, and lingual groove pass to 
these respective borders. The central, fossa is well defined but 
shallower than that of the first molar. The triangular ridges from the 
cusps are well marked and between these the grooves meet forming 

a cruciform sulcus. Occasion- 
ally the tooth has five cusps 
when the anatomy of this sur- 
face is similar to that of the first 
molar. 

The Buccal Surface (Fig. 
80). — This has the same general 
form of that of the first molar, 
but is less complicated because 
of the absence of the fifth cusp. 
It is more convex than that of 
the first molar, is relatively 
Fig. 79--Right Lower Second Molar. smaller in extent and is not so 

Occlusal Surface. 

definitely divided into lobes by 
the buccal groove. This latter usually terminates by blending 
with the buccal surface about its center and rarely terminates in a 
buccal pit. 

The Lingual Surface (Fig. 81). — Except that it is smaller, this 
resembles the lingual face of the first molar crown so closely as to 
require no separate description. 

The Mesial Surface (Fig. 82). — This is more convex than that of 
the first molar but is like it in other respects. 

The Distal Surface (Fig. 83). — The absence of the fifth cusp is 
responsible for the dissimilarity between this and the distal surface 
of the first molar. It resembles, however, the mesial surface of the 
second molar, being slightly more rounded. 

The Roots. — These are two in number and closely resemble the 
roots of the first molar. They are not quite so long, do not exhibit 
the longitudinal depressions seen upon the roots of the first molar, 




THE LOWER SECOND MOLAR. 



51 





Fig. 



-Right Lower Second Molar. 
Buccal Surface. 



Fig. 81. 



-Right Lower Second Molar. 
Lingual Surface. 





Fig. 



-Right Lower Second Molar. 
Mesial Surface. 



Fig. S3. — Right Lower Second Molar. 
Distal Surface. 



52 



THE ANATOMY OF THE HUMAN TEETH. 



terminate in sharper apices and are usually inclined to the distal at 
their extremities. 

The Pulp Cavity (Fig. 84). — The occlusal wall of the pulp chamber 
has only four rudimentary horns, the floor of the chamber is smaller 
and the openings into the pulp canals are closer together but in other 
particulars this is similar to the chamber of the first molar. 

THE LOWER THIRD MOLAR. 

No tooth in the human denture is subject to greater variation than 
the lower third molar. The form most commonly found is that with 
four cusps, in which instance the crown much resembles the second 

molar. Rarely it is possessed of five 

H cusps, being somewhat similar to the 
first molar in form. Often its occlusal 
surface is much broken up and exhibits 
a fossa surrounded by a number of 
cusps and is nearly circular in outline. 
The Surfaces. — When four cusps 
are present, and this is the commonest 
form, the occlusal surface resembles 
that of the second molar except that 
the cusps are shorter, the fossa is 
shallower and the outlines of the sur- 
face are more rounded. When several 
cusps exist the grooves separating them 
radiate from the central fossa. The 
buccal, lingual, mesial and distal sur- 
faces resemble those of the second 
molar if the tooth has four cusps, or 
those of the first if it has five. In 
other forms of the tooth the tendency 
to roundness of these surfaces is to be noted and it is usually difficult 
to perceive any line of demarcation between them. 

The Roots. — There are two which usually resemble the other lower 
molar roots except that they are shorter in proportion to the size of 
the crown, and generally have a marked distal curve which complicates 
the extraction of the tooth. Often the roots are fused and sometimes 
throughout their whole extent, giving thus only one actual root. 

The Pulp Cavity. — It can only be said concerning this that the 
chamber corresponds to the external form of the crown, being similar 
to this cavity of the first or second molar according as the crown re- 



Fig. 84. — Left Lower Second 
Molar. The roots have not been 
completely developed. Longitudinal 
section through mesial root showing 
pulp cavity and method of its division 
into two pulp canals. 



THE DECIDUOUS TEETH. 



53 



sembles one or the other of these teeth. In other instances it is usually a 
rounded cavity resembling the external form of the crown. The 
pulp canals are similar in number to those of the first molar and may 
be found separated even if the roots of the tooth are fused. In rare 
instances a single large canal terminating in a single small apex is 
found. 

THE DECIDUOUS TEETH. 
The temporary or deciduous teeth serve for purposes of masti- 
cation during the earlier years of life and are exfoliated between the 
fifth and the twelfth years to give way to their permanent successors. 




Fig. 85. — The permanent teeth in occlusion. External View. 
(American Text-book of Prosthetic Dentistry.) 

They are less highly developed for functional purposes than the per- 
manent teeth but entirely satisfy the requirements of the food habit 
of these early years. They are necessarily smaller than the permanent 
teeth and are but twenty in number. 

They resemble in many respects the permanent teeth as regards 
external form and internal anatomy, but differ in some particulars 
and these latter must be pointed out. They are in general less well 
developed as to surface markings. They have relatively longer roots 
but these are relatively smaller than those of the permanent teeth. 



54 THE ANATOMY OF THE HUMAN TEETH. 

This latter fact accounts for the constricted neck and bell-shaped 
crown characteristic of the deciduous teeth. The crowns of the teeth 
are shorter in relation to their width than are those of the permanent 
teeth. 

The Upper Central Incisor (Fig. 88). — In addition to being much 
smaller than the permanent central incisor, the crown of this tooth 
is less well marked upon its surface. The labial grooves, the lingual 
marginal ridge and fossa and the distal angle are especially lacking 




Fig. 86. — The Occlusion of the Teeth. Lingual View. 
(American Text-book of Prosthetic Dentistry.) 



in development. Its surfaces are much rounded and its neck is con- 
stricted. The root is relatively longer and smaller than that of the 
permanent tooth but resembles it in other particulars. 

The Upper Lateral Incisor (Fig. 88).— This resembles both the 
permanent lateral and the deciduous central incisor. It has the 
characteristics of the former except in a modified degree. Its surface 
markings are less pronounced than are those of the permanent lateral 
and it resembles the deciduous central except that its width is less and 
its distal angle is more rounded. It is a more delicately shaped tooth 
but is usually equal in the length of its crown to the central and fre- 
quently its root is longer. The latter resembles that of the permanent 



THE DECIDUOUS TEETH. 55 

lateral incisor in other particulars except of course that it is relatively 
smaller. 

The Upper Cuspid (Fig. 88). — The resemblance between this tooth 
and that of the permanent series is marked, but sufficient differences 
exist between them to easily differentiate the two teeth. 

The crown of this tooth is proportionately shorter and more rounded 
than that of the permanent cuspid. The labial surface presents a 
marked labial ridge ascending from the point of the cusp, and the 
labial grooves are much nearer the angles of the tooth. The angles 
of the crown are much nearer the cervical line than those of the per- 
manent cuspid in consequence of which the mesial and distal cutting 
edges are relatively longer and the mesial and distal surfaces are 
smaller. The lingual surface 
has a marked lingual ridge and 
the surface is generally rounded 
and convex. The root is pro- 
portionately smaller than that of 
the permanent cuspid and the 
pulp canal is small in conse- 
quence, but the pulp chamber, 
like that of all the deciduous 
teeth is relativelv lanze ^ IG * ^7* — Occlusal surface of the upper 

' jo' deciduous teeth. 

The Upper First Molar.— 

The molar teeth of the deciduous series are totally unlike their suc- 
cessors, the bicuspids, and partake chiefly of the characteristics of 
true molar teeth. The crown of the first upper molar usually has 
three cusps, two on the buccal and one on the lingual side. 
(Fig. 89.) The surface is almost quadrilateral because the large 
size of the lingual cusp serves to balance the two buccal on the 
opposite side. The corners of the figure are much rounded, the 
sharpest corner being the mesio-buccal while both the lingual corners 
are much rounded. The buccal cusps are sharper than the lingual 
which is full and rounded, although all are more pointed than those 
of the upper permanent molars. A central fossa occupies the space 
between the cusps. It is broad and shallow. A groove passes from 
it to the buccal, mesial and distal sides respectively, and these serve 
to separate the cusps from each other. 

The buccal surface resembles that of the upper • molars except 
that the occlusal margin is sharp, the surface is more rounded, the 
buccal groove is very shallow and poorly defined, and at the cervical 
margin a ridge of enamel passes from the mesial to the distal border. 




50 THE ANATOMY OF THE HUMAN TEETH. 

The lobe of this surface mesial to the buccal groove is proportion- 
ately larger than that of the permanent molar, as it is both wider and 
larger from occlusal to cervical margin than the distal lobe. 

The lingual surface is full and convex in every direction and 
passes into the mesial and distal faces without demarcation. These 
latter resemble those of the upper permanent molars, the mesial being 
flattened with a convexity near the occlusal margin, the distal being 
rounded. 

Three roots are possessed by this tooth. They are mesio-buccal, 
disto-buccal and lingual. The buccal roots are flattened mesio-distally, 




Fig. 88. — Skull showing deciduous teeth in occlusion. 

the lingual being flattened bucco-lingually, and they diverge mark- 
edly in order to give a space for the permanent tooth which succeeds. 

The pulp chamber is rounded and large, corresponding with the 
general external form of the crown. The root canals are small and 
thread-like and difficult to enter. 

The Upper Second Molar (Fig. 89). — This tooth is larger than 
the first temporary molar and resembles the first permanent molar so 
exactly that a separate description is unnecessary. It has not the 
lingual cingule or fifth cusp, it is smaller, more constricted at the neck 
and its roots are widely separated at their apices, but in other particu- 
lars the description of the permanent tooth will suffice. 

The Lower Central Incisor.— Except for the fact that the tooth is 
smaller, has more rounded angles, and has its labial and lingual grooves 



THE DECIDUOUS TEETH. 57 

poorly defined, the description of the permanent tooth would equally 
apply to this. It must be added, however, that its root is relatively 
smaller than that of its successor. 

The Lower Xateral Incisor. — The resemblance between this and 
the upper deciduous lateral incisor is marked. It is wider than the 
lower central and its distal angle is rounded like that of the upper 
lateral. Its various surfaces and its root are like those of its upper 
opponent and further description is unnecessary. 

The Lower Cuspid. — The upper and lower deciduous cuspids 
are much alike. The latter is narrower mesio-distally and its surfaces 




Fig. S9. — Dissected specimen of maxillae and mandible showing the deciduous teeth. 

are not quite so convex but in other particulars its anatomy is identical 
with that of the former. 

The Lower First Molar (Fig. 89).— This tooth has the general 
molar form but a detailed description is necessary for its identifica- 
tion. Its crown is a much rounded cuboid and exhibits four cusps, 
one near each of its rounded angles. On the occlusal surface these 
four cusps are seen to be divided by grooves which unite in the fossae. 
The mesio-buccal cusp is the largest. A ridge descending from it 
anteriorly curves and meets one from the mesio-lingual cusp to form 
a mesial marginal ridge. Triangular ridges from these two cusps 
meet at the bottom of a mesial groove, and a small depression is formed 
between these and the mesial marginal ridge. This is often called 



$8 THE ANATOMY OF THE HUMAN TEETH. 

the mesial fossa but is very small as compared to the distal fossa which 
is located between the two distal cusps and these triangular ridges. 

A distal, a buccal and a lingual groove, all poorly denned, emanate 
from the distal fossa in these several directions. The buccal and lin- 
gual grooves are not continuous because the greater size of the mesio- 
buccal cusp carries the former too far distally. The disto-buccal 
cusp is small, the mesio-lingual is usually the sharpest and longest, 
and the disto-lingual is not well defined as the lingual groove is always 
shallow. The distal marginal ridge is cut by the distal groove. 

The buccal surface is convex and has- near its cervical margin a 
pronounced ridge of enamel, the cervical ridge. The mesial margin 
is longer than the distal in consequence of the greater size and length 
of the mesial lobe, a condition similar to that of the first upper decid- 
uous molar. The buccal groove is shallow and either terminates in 
a pit or disappears upon the center of the surface. 

The lingual surface is convex, and the lingual groove marks its 
occlusal portion about the center when it is present but often it is 
almost indistinguishable on this surface. The mesial and distal sur- 
faces are very similar to those of the second permanent molar. The 
mesial is flat with a pronounced occlusal edge; the distal is more 
rounded and the distal groove usually marks decisively its occlusal 
margin. The tooth has two roots which are similar to those of the 
first permanent molar except that they are smaller and quite divergent 
to give space for the bicuspid which follows. The pulp chamber cor- 
responds in shape with the external surface of the crown. The en- 
trances to the three canals are near together, the two mesial ones being 
small and very difficult to enter, the distal canal being more accessible. 

The Lower Second Molar (Fig. 89). — Beside the constriction 
of its neck, the divergence of its roots, and its smaller size, this tooth 
resembles the first permanent molar in almost every particular. The 
description of the latter tooth will apply to the deciduous tooth and 
the reader is referred to it. 



CHAPTER II. 
THE HISTOLOGY OF THE HUMAN TEETH. 

BY CHARLES R. TURNER, D. D. S., M. D. 

A knowledge of the minute anatomy of the tissues of the human 
teeth is as important as an acquaintance with their surface forms, for it 
paves the way to an understanding of their several physiological rela- 
tionships in the tooth, to a knowledge of the pathological conditions 
arising in them, and to a rational conception of the various operative 
and therapeutic measures used in the treatment of these conditions. 

The tissues of the human tooth are the enamel, which is the hard 
external covering of the crown; the dentin, which composes the bulk of 
the tooth and largely determines its form; the cementum, which forms 
the external covering of the root and to which is attached the peri- 
cementum, a membrane intervening between the tooth and its bony 
socket in the alveolar process; and finally the dental pulp, a mass of 
soft tissue occupying the internal chamber of the tooth called the pulp- 
cavity. 

A clearer understanding of the relationships of these tissues may 
be had if we first become acquainted with the method of their develop- 
ment in the embryo. This also confers a better knowledge of their 
structure. 

About the fortieth to the forty-fifth day of intra-uterine life, there 
is a thickening of the stratum Malpighii of the oral epithelium over the 
site of the future jaw. This forms a band of epithelial cells extending 
from one end to the other in each jaw. About the forty-eighth day a 
budding is seen to take place from the under surface of this tooth-band, 
and ten rounded buds appear attached to it, marking the beginning of 
the tooth-germs for the deciduous teeth. These buds dip further into 
the substance of the underlying connective tissue, and becoming invagin- 
ated upon their advancing surfaces, finally enclose in this invagina- 
tion a mass of mesoblastic connective tissue and become the tooth- 
germ. This epithelial cup which has descended from the mucous 
membrane remains connected with it for some time by a cord of epithe- 
lial cells, the epithelial cord, but this cord soon disappears, and the 
tooth-germ is enclosed by a fibrous membrane developed from the 

59 



6o 



THE HISTOLOGY OF THE HUMAN TEETH. 



surrounding tissue. The epithelial cup becomes the enamel organ of 
the future tooth, the connective tissue enclosed by it becomes the dentin 
organ or papilla. The whole tooth-germ enclosed in its sac is known 
as the dental follicle. (Fig 90.) 

The enamel organ takes on the form peculiar to the tooth which it is 
to assist in forming, and its cells begin to alter in character. Those 




Fig. 90. — Section of upper jaw of human embryo near the seventh month of fetal 
life, showing development of temporary cuspid. A. Ameloblasts showing beginning of 
enamel formation. B. Dentin. C. Showing beginning of dentin formation. D. Walls 
of tooth sac. E. Dentinal papilla. X 5°- (Williams. Dental Cosmos.) 



next to the dentinal papilla become columnar in form, those on the ex- 
terior disappear by atrophy, while the intervening ones are changed 
from polygonal to stellate cells and become the stellate reticulum. 
This latter finally almost entirely disappears, leaving however next to 
the inner columnar layer a small layer of cells which now comes to be 
known as the stratum intermedium. The inner columnar cells now 
become enlarged and elongated, their nuclei move to their outer ends 






THE ENAMEL. 6 1 

and they become the ameloblasts, which are the cells directly concerned 
with the formation of the enamel. 

The dentin organ which occupies the space within the enamel 
organ, and which is formed from the mesoblastic connective tissue, is 
composed of embryonal connective tissue cells of various kinds; spindle 
shaped, round, and stellate cells are scattered through its substance, 
while over its entire periphery there is a layer of specialized club-shaped 
cells, the odontoblasts, which are specifically concerned in the forma- 
tion of the dentin. 

In the development of the tooth, a deposit of dentin initiates the proc- 
ess, a layer of dentin being calcified about the external surface of the 
odontoblastic layer of the papilla. The function of the odontoblasts in 
this process is imperfectly made out. It is known that lime salts 
are deposited about their external processes and that these become 
the dentinal fibrils. Furthermore, as said by Broomell, they are be- 
lieved to superintend the dentin formation, but just what is their rela- 
tion to the deposition of the lime salts is not known. After the dentin 
cap is begun it grows by additions to its interior, while upon its 
periphery enamel formation begins. This is by a process of secretion in 
which globular masses of calco-globulin are formed in the ameloblas- 
tic cells; these escape from the external ends of the ameloblasts and, 
becoming packed together one after another, form the enamel prisms. 
An albumen-like substance, according to Williams, is secreted in the 
stratum intermedium, and flows about the partially formed prisms, 
"supplying the cement substance and probably the mineral matter for 
the calcification of the whole." 

Cementum is formed upon the completed dentin root of the tooth 
by specialized odontoblastic cells, the cementoblasts , which have devel- 
oped in the wall of the tooth follicle. Its growth is similar to that of 
subperiosteal bone. 

The pulp is what remains of the dentin papilla, after the latter has 
been reduced in size by the growth of the dentin walls. The periph- 
eral layer of odontoblasts persists during the life of the pulp, but 
after the mature tooth is formed, these cells remain inactive unless 
called into activity by some pathologic stimulation from without. 

THE ENAMEL. 

The enamel constitutes the external covering of the crowns of 
the teeth. It is by far the hardest of the animal tissues and for this 
reason it is particularly suited to resist the wear incident to the use of 
the teeth in the comminution of food. Its distribution over the crown 



6a THE HISTOLOGY OF THE HUMAN TEETH. 

oi a tooth is not uniform, as it is thinnest at the cervical margin, where 
it is slightly overlapped by the cementum; from this margin it increases 
in thickness, until over the cusps and cutting edges of the teeth, where 
it is most exposed to wear, it is thickest of all. It is also slightly 
thicker at the site of the elevations and ridges upon the crowns of the 
teeth. In the newly erupted tooth it is faintly and delicately ridged 
transversely, and in some teeth it presents other evidences of its develop- 
ment, but it soon wears smooth and lustrous. When a tooth is erupted 
the enamel is entirely completed over the whole of its crown. No 
portion of the tooth is erupted until the- enamel covering it is fully 
formed. When once formed enamel is a fully completed substance, 
and no physiologic change in its structure or composition ever occurs 
thereafter. Williams remarks, "Enamel is a solid mineral substance, 
and the finest lenses reveal not the slightest differences between enamel 
ground moist from a living tooth, and that which has laid in the earth 
for a hundred centuries." 

Defects in the structure of the enamel, in consequence of which the 
value of its protective office is lessened, are commonly observed at the 
site of the fissures and pits upon the surface of the tooth-crown which 
marks the points of union of the several centers from which calcification 
began. These faults are frequently found in the sulci of the molar and 
bicuspid teeth, in the buccal pits of the molar teeth, and in the 
lingual fossae of the upper lateral incisors. These defects are favor- 
able sites for the beginning of caries, the break in the integrity of 
the enamel affording lodgment for the bacteria and a favorable 
starting point for their activity. 

W T hile enamel is formed in an organic matrix, not the least trace 
of this remains chemically in the completed enamel. This accounts 
for the lack of sensitivity of this structure, for it is not capable of trans- 
mitting physiologically any sensations whatever. These facts demon- 
strate its value as a vital protective covering for the teeth. 

Chemically it consists chiefly of the phosphate and carbonate of 
calcium as the following analysis by von Bibra shows: 

Man. 

Calcium phosphate and fluorid, 89.82 

Calcium carbonate, 4.37 

Magnesium phosphate 1.34 

Other salts, 88 

Cartilage 3.39 

Fat, 20 

Organic, 3.59 

Inorganic 96.41 



Woman 

81.63 

8.88 

3-55 

•97 

5-97 

a trace 


5-97 
94-03 



THE ENAMEL. 63 

Charles Tomes has shown that the organic matter obtained in this 
and the older analyses is simply the water which is combined with 
the lime salts. He has proven that it will be suddenly given off upon 
ignition of the specimen under analysis. 

Enamel is not a homogeneous mass of calcified tissue but, under 
the microscope may be seen to consist of a collection of prisms or rods, 




Fig. 91. — Section of enamel of human tooth near line of dentin. Shows enamel rods in 
cross- and longitudinal section. X 1000. (Williams. Dental Cosmos.) 

five and six sided, which are united together by means of a cementing 
substance. (Fig. 91.) As it contains no organic matter whatever and 
has resulted from the completed calcification of the matrix in which 
it is formed, we find no chemical remains of the matrix, but the tissue 
exhibits structural evidences of its mode of formation. Generally 
speaking the enamel rods are arranged so that they begin at right angles 
to the surface of the dentin, from which they extend to the external 
surface of the tooth. In the cervical region they incline somewhat 



04 



THE HISTOLOGY OF THE HUMAN TEETH. 



downward in the direction of the root, but as the lower third of the 
crown is reached they pass horizontally outward, becoming more in- 
clined occlusally as the cusps and the cutting edges of the teeth are 
reached, in which positions they are largely parallel to the long axis 
of the tooth. (Fig. 92.) The ends of the prisms are thus exposed to 
the wear of these surfaces. 

While a majority of the rods extend from dentin to surface, it will 
be seen that as the surface area of the latter is greater than that of the 
former, and as the rods are practically of the same diameter at each end, 




Dentin. 



Enamel. 



Fig. 92. 



-Section showing dentino-enamel juncture, the direction of the enamel rods 
and primary curvatures of dentinal tubules. (Broomell.) 



additional rods are required to fill in the interspaces in this fan-like 
arrangement. These additional rods begin between the other long 
rods and extend outward toward the surface of the tooth. While the 
rods pursue in general an almost straight course, in all instances 
they are slightly curved and in some cases they are much contorted and 
twisted, and when this is marked the enamel is usually spoken of as 
"gnarled." 

The rods are not of uniform diameter throughout their whole ex- 
tent, as each rod presents a number of varicosities w T hich increase its 
size. (Fig. 93.) These varicosities vary in different specimens of en- 
amel but they are present in all. The enlarged portion of one rod is 
opposite to that of the adjacent rods, and they do not alternate as 






THE ENAMEL. 65 

would seem the more natural arrangement. The reason for this, is 
the fact that the globules, of which the rods are made and which are 
responsible for the varicosities, were deposited simultaneously. The 
varicosities do not as a rule appear so pronounced in the enamel next 
the dentin, but elsewhere in any given specimen they are of about uni- 
form occurrence. The space between the rods is filled in with a more 
transparent but not more highly calcified cement substance. Wil- 
liams has shown a specimen in which the globules composing the rods 
do not appear continuous but seem united with this cement substance 
as the rods are united to each other. It is very probable that this is 




Fig. 93. — Enamel rods showing varicosities and striae of Retzius. A. Brown striae 
of Retzius. B. Enamel rods showing varicosities. X 200. (Williams. Dental Cosmos-) 

due to the refraction of the light by the rod substance, as longitudinal 
sections of the rods normally exhibit under the microscope a series of 
light bands, the so-called " striation" of the rods, which may be brought 
into view or made to disappear by slightly changing the focus and 
were formerly believed to have some structural significance. 

Another appearance presented by the enamel rods under the micro- 
scope is illustrated in Figure 94. In this it will be seen that bands of 
darker enamel alternate with those of lighter, thus dividing it into strata. 
This stratification of the enamel is due to the fact that small quantities 
of pigment have been laid down at various stages in its development, 
and they simply mark the exterior of the crown at the time they were 
laid dowm. They are in reality incremental lines and mark successive 
stages in the growth of the enamel. They are usually spoken of as the 
5 



66 



THE HISTOLOGY OF THE HUMAN TEETH. 



"brown striae of Retzius." They begin at the summit of the already 
formed dentin and extend in curves toward the cervix. The addition 
of more dentin at the developing end of the tooth gives more surface 
for enamel to be deposited upon, and another stratum of enamel is 
formed covering the already formed enamel. The enamel formation 
at the occlusal end of the crown is completed before that at the cervix. 




Fig. 94. — Longitudinal section of human enamel showing globules. Polarized 
light. X 3°°- (Williams. Dental Cosmos.) 



These facts explain why the incremental lines are neither parallel to 
the external surface nor to that of the dentin. 

The "lines of Schreger" are another characteristic of fully formed 
amel. They are not visible by transmitted light but can be seen by 
enflected light as Fig. 95 shows. They are said to be edu " to thevarious 
reections assumed by the contiguous groups of enamel rods. " * 
dir The physical characters of enamel, which are interesting from 

*Broomell: Anatomy and Histology of Mouth and Teeth, 1902, p. 395. 






THE ENAMEL. 



67 



the standpoint of filling operations upon the teeth, are more readily un- 
derstood when they are viewed in the light of the histology of the tissue. 
Mature enamel forms a hard covering for the crowns of the teeth 
which will resist a large amount of force upon it. The enamel rods fit 
closely together and the intervening tissue is highly calcified and binds 
them together. Thus they give each other lateral support, and unless 
there is a break in the enamel surface, it is very difficult to fracture or 
crush them. In addition, their inner ends rest upon the dentin, a 
slightly elastic tissue, which gives them a firm support. It is upon 
these two facts that the ability of the enamel to resist physical force 



Brown striae 
of Retzius. 



Lines of 
Schreger. 



/ 






mm 


$■•&*£* +wmaf :^B \r Hr 









Enamel. 



Dentin. 



Fig. 95. — Section showing striae of Retzius or incremental lines of the enamel 
and the lines of Schreger. (Gysi. Broomell.) 



largely rests. If, however, there is a break in the enamel surface, then 
it is an easy matter to split off the enamel rods immediately adjacent to 
the break, and especially is this true if the enamel so split is not sup- 
ported upon mechanically sound dentin. While the enamel is intrin- 
sically of a high degree of hardness, yet it has a natural cleavage, 
and the line of this is along the interprismatic substance, so that the 
line of cleavage is approximately parallel to the direction of the prisms. 
Occasionally it breaks transversely through a prism here and there, 
but never along the central axis of the prism. The lesson these facts 
teach in the preparation of cavities for filling operations is that the en- 
amel at their margins must be supported upon dentin, and that these 



THE HISTOLOGY OF THE HUMAN TEETH. 

margins must be formed so that no prisms which do not reach the 
dentin are allowed to remain. This requires that the cavity margins be 
beveled at the expense of prisms which are firmly seated upon the den- 
tin, and a knowledge of the direction of the enamel prisms is neces- 
sary in preparing the cavity margins. 

Black* has shown that enamel possesses less strength than the 
dentin, as to resistance to both tensile and crushing strains. Therefore 
the retentive portions of cavities should be made in the dentin, and the 
mechanical force used in the insertion of gold fillings should be slight 
upon enamel margins. He has also shown that where several thick- 
nesses of gold were placed between the instrument and the enamel, 
that the crushing effect of impact is greatly reduced. 

THE DENTIN. 

The dentin composes the bulk of the tooth, and contributes to its 
form and strength. It surrounds the pulp and protects this from injury, 
it gives support to the enamel covering the crown, and upon its root por- 
tion is deposited the cementum which affords attachment to the retentive 
tissues of the tooth. Normally no part of it appears upon the external 
surface of the tooth, and when here present is exposed from some error 
in the development of the tooth or from some break in the enamel or 
cementum. It is light yellow in color, although it varies slightly in 
shade in different specimens, and it has somewhat the appearance of 
ivory or bone. 

Histologically it is a highly developed connective tissue, and con- 
sists of a partly calcified organic matrix traversed by a system of tubules, 
the contents of which is protoplasmic in character. As it is impossible 
to remove the contents of the tubules no chemical analysis has been 
obtained of the matrix proper. Von Bibra gives the following as the 
constituents of a specimen of thoroughly dried dentin: 

Organic matter (tooth cartilage), 27.61 

Fat, 0.40 

Calcium phosphate and fluorid, , 66.72 

Calcium carbonate, 3.36 

Magnesium phosphate, 1.08 

Other salts 0.83 

When the tissue is decalcified by the use of strong acids, the re- 
maining organic matrix yields gelatin on boiling, while that portion 
immediately surrounding the tubules which differs from the body of the 
matrix in resisting strong acids and alkalies, yields elastin on boiling 

*The Dental Cosmos, Vol. xxxvii, page 414. 






THE DENTIN 



6 9 



(Noyes). Opinion differs as to whether this is more highly calcified 
than the surrounding matrix. Under the microscope it has a different 
refractive action upon light as the accompanying high-power field shows 
(Fig. 96). These are known as "the sheaths of Neumann," and sur- 
round the protoplasmic contents of the tubules. 

The matrix itself is practically structureless and homogeneous 
in character. The tubules traverse it from the pulp-cavity, to the 
external surface of the dentin. (Fig. 97.) They begin by a funnel-like 
opening in the pulp-cavity wall, and extend in curves outward to near 
the surface of the dentin where they usually branch and anastomose 
freely. They are of practically uniform caliber from beginning to end, 




Fig. 96. — Dentin showing tubules in cross-section. Dt. 
Dentin matrix. S. Shadows of sheaths of Neumann. (Noyes. 
Operative Dentistry.) 



Dentinal tubules. D. 
American Text-book of 



and as the external surface-area of the dentin is greater than that at the 
pulp-cavity, the tubules are closer together at their beginning from the 
latter than at the external surface, and diverge almost imperceptibly in 
passing outward. They exhibit long graceful curves in their course 
outward. In the crown of the tooth the tubules exhibit what have been 
designated their primary and secondary curvatures. The tubules be- 
gin at right angles to the surface of the pulp, and reach the surface 
of the enamel at a right angle to it. Between these points they present 
a reversed curve or ogee. The secondary curvatures are perceptible 
throughout the extent of the tubule and are due to the fact that the 
tubule has a general spiral direction through the dentin. In the root 



70 THE HISTOLOGY OF THE HUMAN TEETH. 

portions of the teeth the tubules pursue almost a straight course from 
the pulp to cementum, which in general is perpendicular to the long 
axis of the tooth. In the apical region they are arranged radially. 
At or near the external end they branch out and anastomose freely. 
Inasmuch as it is along the line of the tubules that the infection travels 
in caries, this arrangement explains how caries may progress along the 
dento-enamel juncture and how the enamel is undermined. This also 
explains the greater sensitivity of the tooth at the dento-enamel junc- 
ture, a clinical fact of common knowledge. 

The dentinal tubules contain a protoplasmic mass, the dentinal 
fibrils, which extend from the odontoblastic layer of cells on the ex- 




FlG. 97. — Transverse section through root of human molar showing the curvature of 
the dentinal tubules about the pulp canal. X 4°- (Broomell.) 



ternal surface of the pulp. These are usually called the -fibers of 
Tomes. Beyond the fact that the fibrils are processes of the odonto- 
blastic cells, nothing yet is definitely known about the manner of their 
connection with the nerves of the pulp, nor about the way in which 
sensory impulses are transmitted by them. Unlike the enamel the 
dentin is a sensitive tissue and has physiologic connection with the 
organism. The dentinal fibrils conduct sensory impulses and it is 
believed that in some way the dentin is nourished through the con- 
tents of the tubuli. One reason for a belief in the latter is the fact as 
brought out by Black that the dentin of old teeth has a higher percentage 



i 



THE DENTIN. 



71 



of lime salts than that of young teeth. The growth of the dentin is not 
completed with the eruption of the tooth, for all of its root is not 
formed at this period, but continues for some time afterward. The 
root is completed and the pulp becomes reduced in size, successive 
layers of dentin encroaching on the pulp-cavity. In the mature 
tooth the process of dentin formation remains at a standstill until 
old age, when it will be found that the pulp-cavities are reduced to 
very small dimensions. 

The odontoblasts may be stimulated into activity by irritation from 
the encroachments of carious cavities or by a wearing away of the 



Cementum 




Dentin. 



Fig. 



-Interglobular spaces in the dentin. X 60. (Broomell. Dental Cosmos.) 



tooth substance from abrasion or erosion. Dentin is deposited on the 
pulp-cavity wall immediately in relation with the site of the irritation 
and is an expression of a self-protective activity of the pulp. Dentin 
thus deposited is known as secondary dentin. It is of poorer structure 
than normal dentin and not typical in the arrangement of its tubules, 
which present many interruptions. 

At the dentino-cemental juncture the dentin presents under the 
low powers a somewhat granular appearance, and this area is known 
as the granular layer of Tomes. (Fig. 98.) It consists of the so-called 
interglobular spaces, which are erroneously so named as in the fresh 



7- 



THE HISTOLOGY OF THE HUMAN TEETH. 



specimen they are not spaces but are areas of imperfectly calcined dentin. 
They are filled with protoplasmic tissue through which the dentinal 
fibrils may be made out. In the dried specimen they appear as spaces 
because of the desiccation and contraction of their protoplasmic con- 
tents. These so-called interglobular spaces are often found else- 
where scattered through the dentin, usually occupying positions cor- 
responding to a stage in the development of the dentin. 

THE CEMENTUM. 

Histologically considered cementum ia very closely related to sub- 
periosteal bone both in its structure and development. It forms the 
external covering of the roots of the teeth, serving as a medium of at- 
tachment between the pericementum and the dentin. At the cervical 




Fig. 99. — Cementum from cervix of adult tooth. X 4°- (Broomell.) 



margin, it abuts upon the edge of the enamel or slightly overlaps it, 
and at this point is thinly distributed over the surface of the root. It 
increases in thickness as the apex of the ro6t is reached and the mature 
tooth is of considerable thickness in this region. 

While its structure resembles that of bone in many particulars, 
it differs in having no Haversian system and is easily distinguished 
from it under the microscope. It presents for examination a matrix 
of partially calcined organic material containing lacunaz and canalic- 



THE CEMENTUM. 



73 



uli. The matrix or ground-substance is similar in structure and com- 
position to that of bone. The lacunae are spaces scattered through 
the matrix which are occupied in the recent specimen by the cement 
corpuscles, which are cement-forming cells or cementoblasts which 
have become encapsulated during the calcification of the tissue. The 
canaliculi extend from the lacunae and transmit the processes of the 
cement corpuscles. Beside these elements the tissue contains the 
cement fibers which are calcified fibers of the pericementum. It is 
developed by the deposit of successive lamellae upon the dentin surface 
and these are visible under the microscope as its incremental lines. 



..V 



1MM ; 






SrtSSWM 



m ■ m 






^k' 



mmmm 







Fig. ioo. — Cement corpuscles of the outer strata. X 4-0- (Broomell.) 



The character of the tissue varies with its position upon the root and 
with the period of tooth development at which it is formed. 

The matrix next to the dentin is more nearly homogeneous than 
elsewhere. Under the microscope it appears somewhat granular 
and is characterized by the absence of lacunae and canaliculi. (Fig 99.) 
This is also largely true of the whole thickness of the cementum near 
the cervical margin as lacunae are infrequent there. The lamellae making 
the successive additions to the tissue increase both in number and thick- 
ness as the apex of the tooth is approached, and the lacunae become 
more abundant in them. 

The cement corpuscles which occupy the lacunae are masses of 
protoplasmic tissue which are the remains of cementoblasts. They 






74 THE HISTOLOGY OF THE HUMAN TEETH. 

arc most abundant in the middle layers of the cementum, are absent 
in the portion next the dentin, and are infrequent in the outermost 
layers. (Fig. ioo.) Their processes are usually directed toward the 
outer surface of the tooth, and these occupy the canaliculi above re- 
ferred to. 

Another element of the cementum which is the most variable of its 
histological constituents is the cement fibers. (Fig. 101.) These, 
according to Black, are principal fibers of the pericementum which 
have been caught in the developing tissue and calcified. In some 
rare instances they mav be observed to extend from the innermost 




X 




Fig. ioi. 



-Cemental fibers of the middle strata. X 60. 
(Broomell. Dental Cosryos.) 



layer uninterruptedly through to the surface, but they are usually of 
much shorter extent. Sometimes they correspond in length only to 
the thickness of one lamella and sometimes to that of two or more. 
This variation is due to the manner of growth of the cementum and 
to the fact that the attachment of the pericementum is constantly 
varying, the fibers being frequently cut off and reattached at different 
positions. Thus the cement fibers which terminate at the surface 
of a lamella are those whose attachment has been altered at the com- 
pletion of the lamella. The fibers are of most frequent occurrence in 
the apical two-thirds of the tissue and in the central strata of this re- 



THE PULP. 75 

gion. Broomell has called attention to the presence of fibers in bun- 
dles in the oldest lamella, the bundles being arranged radially to the long 
axis of the tooth. The fibers which extend from the dentin do not 
have any direct connection with it, but usually terminate here by break- 
ing up into fibers which run more or less parallel to its outer surface. 
This is to be expected when the method of cemental developement is 
remembered. 

In some of the multi-rooted teeth the cementum bridges over the 
gap from one root to the other, building in the space solidly. Usually 
some evidence in the way of cement cells or mesoblastic tissue remains 
to show where the extensions from each root have united. In this 
type of tissue the lamellae are poorly marked. 

The formation of cementum goes on more or less constantly 
during life, as cementoblasts are constantly present in the perice- 
mentum next to the tooth. In youth the cementum is thin as com- 
pared to that found in adult life and in old age. 

The cementoblasts are sometimes called into activity after the tooth 
is formed by some pathological excitant, and this condition is known 
as a hyper-cementosis of the tooth. The tissue thus formed may be 
of such extent as to complicate the extraction of the tooth, or it may 
press upon the nerves leading to the pulp or to that of some other tooth 
and cause obscure pains which are difficult to recognize clinically. The 
pathologic cementum is usually upon the apical portion of the tooth, 
and is not typical histologically. 

Union occasionally occurs between the roots of different teeth by a 
fusion of the cementum in a manner somewhat similar to that in which 
the roots of a tooth unite. This gives rise to the so-called fused teeth 
which are occasionally found. 

THE PULP. 

The dental pulp consists of the soft tissues occupying the central 
cavity of the tooth known as the pulp-cavity. It is the somewhat 
changed remains of the dental papilla, the formative organ of the den- 
tin. It is composed of soft embryonal connective tissue, odontoblastic 
cells, blood vessels, and nerves. No lymphatics exist in the pulp — a 
fact of pathologic interest. It has two functions, the formation of the 
dentin, a function practically quiescent in the adult tooth, and the 
nutrition and innervation of the dentin. 

The odontoblasts, through the medium of which the dentin is formed, 
are a layer of cells occupying the entire periphery of the pulp and in 
close relation with the dentin. (Fig. 102.) They exist as a single layer 



76 



THE HISTOLOGY OF THE HUMAN TEETH. 



of cylindrical cells during the formative period of the tooth and until 
late life, when they become rounded or spheroid. They possess three 
kinds of processes which are usually referred to as dentinal, lateral, and 
put pal. The dentinal processes, of which there is only one to an odon- 
toblast (occasionally two may be found), are the dentinal fibrils or 
fibers of Tomes which enter the dentinal tubules; the lateral processes 




Fig. 102. — Section of developing tooth of human embryo near seventh month of 
fetal life. F. Ameloblasts. H. Dentin. I. Odontoblasts. B. and C Cells of reticulum 
of enamel organ. D. Stratum intermedium. X *75- (Williams. Dental Cosmos.) 



are numerous and by this means the odontoblasts are connected to 
each other; the pulpal processes extend into the "layer of Weil", 
a transparent layer of tissue in relation with the pulpal ends of the 
odontoblasts, and there become lost to view. The odontoblastic 
cells have large, oval, deep-staining nuclei situated near the pulpal ex- 
tremity of the cells. This layer of odontoblasts is often called the 
membrana eboris. 



THE PULP. 



77 



The layer of Weil, situated just below the odontoblasts, is a trans- 
parent layer of tissue containing very few connective tissue cells, and 
then below this comes the main body of the pulp tissue. (Fig. 103.) 
This is composed of connective tissue cells, which may be either stel- 
late or spindle-shaped, with a large mass of intercellular substance, 







%; ; ,r '^#^#i 




Fig. 103. — Section of developing tooth of embryo calf. A. Stellate reticulum. B. 
Stratum intermedium. C. Ameloblasts. D. Dentin. E. Odontoblasts. F. Blood 
vessels with corpuscles in situ. X 275 (Williams. Dental Cosmos.) 



together with a few round cells which Noyes says "are probably young 
cells which have not yet acquired the adult form." 

The blood vessels of the pulp communicate with the general cir- 
culation through the apical foramen or foramina of the tooth. One 
or more small arterial trunks enter the pulp-cavity at the apex and, 
coursing occlusally through the center of the tissue, give off many 
branches. Near the occlusal end of the pulp they further divide into 
capillaries and form a line plexus around the peripheral portion of the 
pulp. The blood vessels are generously distributed through the tissue. 



;S THE HISTOLOGY TO THE HUMAN TEETH. 

The veins form a similar plexus and a contral vein analogous to the 
artery receives the blood from these many venules and conducts it 
through the apical foramen. 

Especial interest attaches to the thinness of the walls of the pulpal 
vessels. The arteries are almost entirely without the external fibrous 
coat and the muscular layer is represented by a single involuntary 
fiber, while the veins have only a single layer of endothelial cells to 
form their walls. For this reason the pulp is particularly unable to 
resist any tendency to hyperemia, and as the tissue is confined in a 
cavity with unyielding walls, the pulp-cavity, and as the apical exit 
from it is small and easily blocked, hyperemia of the pulp is attended 
with a greater amount of pain than in any part of the body, because 
the nerves are easily stimulated by the pressure of the blood in the pulp- 
cavity. When inflammation supervenes and inflammatory products 
are to be removed, the absence of lymphatics further adds to the diffi- 
culties of the situation. These facts explain the observed clinical 
experience associated with pathological conditions of the pulp. 

The nerves of the pulp are transmitted through the apical foramina 
together with the blood vessels. Several bundles of medullated nerve 
fibers enter the foramen and break up into a plexus of nerves which are 
widely distributed through the pulp tissue. Just below the layer of 
Weil, the fibers may be seen to lose their medullary sheath, when they 
penetrate this and are lost between the odontoblasts. None have been 
traced into the dentinal tubules. The sensory nerves of the pulp are 
only capable of transmitting sensations of pain, which may arise from 
mechanical, thermal, or chemical stimuli. It is not possible to localize 
these sensations to any particular tooth, so that one is not able to refer 
them to the tooth in which they arise. Pain originating in one tooth 
may be referred to any other in either the upper or lower series. 

It has been said that the pulp had for its function the nutrition and 
innervation of the dentin. While dentin is of course a non-vascular 
tissue, the physical differences in new dentin and that which is found 
in an old tooth are often so great as to warrant the belief that in some 
way it may be changed after it has formed. This of course can only 
be through the medium of the protoplasmic contents of the tubuli, 
but how this occurs if at all is still only a matter of conjecture. 

This is also true of the sensory innervation of the dentin. The 
dentin is sensitive to stimuli of a chemical, mechanical or electrical 
nature, and the dentinal fibrils are instrumental in delivering these. 
No nerve fibers have been traced into the tubules, but nerve endings 
are closely associated with the odontoblasts. It is believed that the 



THE PERICEMENTUM. 79 

dentinal processes of these cells in some way transmit the stimuli. 
Of course with the removal or death of the pulp, all sensitivity of the 
dentin ceases. * 

THE PERICEMENTUM. 

The fibrous membrane intervening between the root of the tooth 
and the alveolus is known as the pericementum or peridental mem- 
brane. While not a tissue of the tooth proper, it serves to connect it 
with the osseous skeleton and performs so many functions associated 
with the tooth that it deserves especial attention. 

It is composed chiefly of white fibrous connective tissue, and be- 
sides containing the blood vessels and nerves necessary for its proper 
functioning, contains a variety of other cellular elements, the functions 
of which will be discussed later. The chief office performed by the 
pericementum is the retention and support of the tooth in its socket, in 
addition to which it has a developmental and nutritive relation to the 
cementum and the alveolus, and serves as the touch-organ of the tooth. 
Inasmuch as the fibrous elements of the membrane are in predomin- 
ance and as they are related to its chief function, they will be described 
first. 

The fibrous tissue of the pericementum is of two kinds — first, the 
principal fibers, so called by Black because they were greatest in num- 
ber and most important in function, which extend from the cementum 
to the alveolar wall or into the gum tissue and are attached to each; 
and second, the interfibrous tissue, which is the fibrous tissue com- 
posed of spindle-shaped and stellate cells which intervenes between 
the principal fibers themselves and between these and the other perice- 
mental elements. These fibers pass from the tooth to the alveolar 
wall in all portions of the socket, their ends are firmly built into the 
cementum at one end, in which they are spoken of as Sharpey's fibers, 
and into the bone of the alveolar process at the other, and they me- 
chanically support the tooth in its socket. Their arrangement is 
somewhat different in different parts of the membrane and so it will 
be necessary to give their direction in its various portions. In the 
gingival portion of the membrane, where they are thickest, they extend 
from the cementum in three directions. (Fig. 104.) One set passes 
occlusally into the gingivus to support this and make it hug the neck 
of the tooth, and another passes over the alveolar border to blend 
with the fibers of the muco-periosteum of the alveolar process. These 
two sets of fibers are in greatest abundance on the lingual side of the 
teeth, serving to protect this against violence from food in mastication. 



So 



THE HISTOLOGY OF THE HUMAN TEETH. 



The third set of fibers passes almost horizontally outward and they are 
either attached to the alveolus, or on the proximal sides in young sub- 
jects they pass over to the adjoining tooth and become continuous 
with its pericemental fibers. Of this third set of fibers, some pass 
radially directly to the alveolar bone, and on the lingual side these 
are most numerous, while others after leaving the cemental surface 
pass tangentially in bundles, and are attached to the process at points 
mesial or distal to where a radial direction would have taken them. 




Fibers 



Fig. 104. — Section showing pericemental fibers attached to the cementum. (Broomell.) 



These fibers serve to prevent the rotation of the tooth about its long 
axis, while the radial fibers resist force tending to move it laterally. 
In the membrane intervening between the gingivus and the apex 
of the root, the principal fibers pursue either a straight horizontal course 
from cementum to bone or they are directed occlusally. The effect of 
this arrangement is to swing the tooth in its socket, as it were, and it 
enables the tooth to resist the force of mastication or any other which 
tends to depress it in its socket. (Fig. 105.) 



THE PERICEMENTUM. 



8l 



In the apical region the principal fibers extend radially from the root, 
spreading out from it in all directions to the alveolar socket. 

The interfibrous tissue fills in the spaces between the principal 
fibers which is not occupied by the blood vessels and nerves and the 
special cellular elements presently to be described. 

This arrangement of the fibers of the pericementum is remarkably 
adapted to hold the tooth in its socket, to enable it to resist stress placed 







ffll^m, ■' ' i^iiC^ 






\W . I*; f 












fiwi^- Tic, w&W'Mm 

l« <^ t mm 


* feSw 






Kff. ' v . "«■ 






| 


y i 


mm:- ,^Wl 












19 









Fig. 105. — Section through alveolus and root of lateral incisor near the gingivus 
showing direction of fibers of pericementum. A. Pulp with blood vessels and nerves. 
B. Dentin. C. Cementum. D. Alveolar process. E. Interfibrous portion of perice- 
mentum. (Noyes. Angle's Orthodontia.) 



upon it, and yet to yield slightly to the stress and thus to break the force 
of the latter. While the fibrous tissue is of the inelastic variety, the 
fibers are not on tension all the time, and thus permit a certain elasticity 
to the tooth. This elasticity is contributed to in the young membrane 
by the blood vessels, which are very numerous, a condition which 
has a cushioning effect upon the tooth. This elasticity permits the 
slight movement of teeth when separating them for operative pro- 
cedures and in the beginning of their orthodontic treatment. 
6 



82 THE HISTOLOGY OF THE HUMAN TEETH. 

The cellular elements are fibroblasts, cementoblasts, osteoblasts, 
osteoclasts, and certain epithelial structures. 

The fibroblasts are long, spindle-shaped cells found in greater num- 
bers in the young membrane and almost absent in that of old age, and 
are for the repair of the fibrous tissue. They may be observed in the 
bundles of principal fibers. 

The ccmcntoblasts which are concerned with the formation of the 
cementum, are flat, scale-like cells found on the surface of the ce- 
mentum occupying spaces between the principal fibers. They are irreg- 
ular in outline as is shown by Fig., a drawing by Black of cemento- 
blasts isolated by teasing. The depressions in their periphery are 
occupied by fibers. They have oval nuclei and are difficult to find in 
longitudinal sections. 

The osteoblasts are situated upon the alveolar wall which they assist 
in forming. They are spherical cells with round nuclei like odonto- 
blasts elsewhere found in periosteum. They build the bone around the 
fibers of the pericementum, thus strongly attaching it to the bone, and 
the calcified fibers are here also known as Sharpey's fibers. 

The osteoclasts are not constantly present in the pericementum, 
but are found when absorption of the calcified tissues is in progress. 
They are often spoken of as "giant cells" because of their size and the 
great number of their nuclei of which as many as twenty-five are some- 
times found. They are capable of acting upon bone, cementum or 
dentin. Although the exact manner in which they remove the calci- 
fied tissue is not known, it is necessary for them to be in contact with 
it and they are found in the bay-like excavations which they have pro- 
duced. These excavations are known as "Howship's lacunae." 

The epithelial structures of the pericementum were first described 
by Black, who referred to them as the glands of this tissue. While 
their glandular character has not been demonstrated, they resemble 
the glandular tissue in that they are chains of cells epithelial in all 
characteristics which are distributed throughout the membrane. 
Occasionally they appear arranged in a tubule having an impercepti- 
ble lumen, but no connection with the oral epithelium has been traced. 
They are fairly uniformly distributed through the membrane accord- 
ing to a diagrammatic plan by Dr. Black. 

The blood vessels of the pericementum are numerous and are de- 
rived from three sources. Two or three branches are given off by the 
artery of the pulp before it enters the apical foramen. These anas- 
tomose with branches of arteries from the alveolar process and with 
others from the mucous membrane at the gingival margin, forming a 



THE PERICEMENTUM. 83 

plexus of arteries which bountifully supplies the membrane. These 
are more numerous in the young specimen and occupy approximately 
the center of the tissue, but decrease in number and size as life ad- 
vances and in old age are found in channels upon the alveolar wall. 
The nerves are derived in a similar manner from those entering the 
pulp, from the bone itself and from the mucous membrane at the gin- 
givus. They unite and give the tissue an abundant nerve supply. The 
medullated fibers terminate without special nerve endings. They 
transmit sensations of pain and ordinary sensation and thus the peri- 
cementum is the touch-organ of the tooth. 



CHAPTER III. 

HYGIENE AND ARRANGEMENT OF LIGHT IN THE 
OPERATING ROOM. 

BY C. N. JOHNSON, M. A., L. D. S., D. D. S. 

The hygiene and control of light in an operating room is a very 
important matter, affecting as it does the health and comfort of the 
practitioner. In an office where the dentist is confined chiefly to 
operating, as is the case in so many today, it is essential that some 
attention be given to the room where the working hours are mainly 
spent. It is undoubtedly true that many dentists have seriously 
impaired their health and shortened their years of usefulness by con- 
fining themselves in an abnormal environment, and the subject is 
worthy the careful study of every operator. 

The first essential in an operating room is good ventilation and 
sunlight. The operator should not stand in a draft but he should have 
plenty of fresh air and not breathe the vitiated atmosphere so fre- 
quently found in dental offices. The admission of sunlight is very 
important if it can be so arranged without taxing the operator's eyes, 
though this is not always possible with the location of many of our 
offices. Sunshine is a great purifier and is worthy of more consider- 
ation in this respect than it usually receives. 

There is a difference of opinion among practitioners as to which 
is the preferable light for operating, very many urging the advantage 
of a north light, but this has the limitation of not admitting the sun. 
It would seem that the best arrangement was to have a corner room 
for operating with two windows in it one for the operating chair and 
the other to admit sunlight. A north-west room lets in the sun only 
in the afternoon and in the summer is very hot, and the same may be 
said of a south-west exposure. A north-east room is better, having 
the chair face the north window with the east window at the operator's 
back. But this room admits very little sunshine in the winter 
months when it is most needed. What is probably the best arrange- 
ment is to have a south-east exposure with the chair facing the east. 
The sun is usually so high by the time operating begins that it does 
not interfere with the work, and in summer it is so far north that it 

85 



86 HYGIENE AND ARRANGEMENT OF LIGHT 

docs not shine in the south window sufficiently to cause undue heat. 
During the winter months it pours into this window, flooding the 
operating room, coming in at the operator's back, and therefore not 
injuring his eyes by causing too bright a light to shine in front of him. 

This is a very important consideration which many practitioners 
overlook — the avoidance of too much light for the operator to face. 
There is a constant tension on the eyes when the individual is looking 
toward a light, and this is equally true of a reflected light which enters 
from the rear and is thrown back in the face by a bright wall in front. 
This makes it very essential that the color of the walls in an operating 
room should be such as to absorb light and not reflect it. Bright 
colors are to be avoided in decorating, and this one room of all others 
should be given over to service rather than to attempt to make it 
attractive by the use of light shades. Fortunately it may be made 
comfortable to the eyes without sacrificing artistic beauty if the proper 
colors are selected. Where paper is used on the walls it should be a 
solid color without pattern. Green is a suitable shade as also is the 
deep brown known as chocolate. The latter produces a soft, restful 
effect in a room, unobtrusive in any way, and unobjectionable from 
an artistic sense. 

The size and location of the window in front of the operating chair 
are important factors in securing effective light without eye strain. 
The window should be sufficiently high to carry the light directly 
down from the sky into the patient's mouth w T hen the head is tipped 
slightly back, and there should be nothing to interfere with the direct 
passage of the rays such as trees in front of the window or tall buildings 
standing too near. A very common error made by practitioners is 
the admission of too much light in the operating room. The idea 
seems to prevail that the more light the better, but this is a serious 
mistake. It is true that a very excellent quality of light is required, 
and in the immediate vicinity of the patient's mouth the light cannot 
be too strong short of sunshine. But this is the only vicinity where 
it is needed and the diffusion of light over a wide area by having a 
very large window in front of the chair is a severe tax on the eyes which 
few operators realize. If a window is too large some of the light 
should be shut off with a shade, and this is particularly true where 
the window runs down so near the floor as to flood the lower part of 
the room with light. The operator is looking downward much of the 
time and this flood of light is reflected in his eyes. In any arrange- 
ment of an office whereby an operator must use one window for oper- 
ating and face another as he stands at his chair he should cut off every 



IN THE OPERATING ROOM. 87 

ray of light from the window he faces by a dark shade, and in the same 
connection he should avoid anything on the wall in front of him which 
will reflect the light in his face. A bay window while very alluring 
to some practitioners is extremely bad unless the window looking 
toward the operator's face is heavily shaded. The only direction 
from which it is permissible to admit light to the room except that 
which comes straight to the patient's face is at the operator's back, 
and as has just been intimated there should be nothing in front of 
him which would reflect this light back in his eyes. 

Many operators go on year after year suffering eye strain and 
unconscious of the cause of their discomfort through ignorance of the 
essentials necessary in the arrangement and control of light in the 
operating room, or through carelessness in carrying them out. When 
it is considered how important the eyesight of the dentist is it would 
seem only a reasonable supposition that every operator should give 
some attention to a matter so vital to his future comfort and usefulness. 
The essentials are simple and are capable of being carried out in a 
reasonable degree at least by every practitioner. 



CHAPTER IV. 
ASEPSIS IN THE OPERATING ROOM. 

BY A. E. WEBSTER, M. D., L. D. S., D. D. S. 

Under this heading must be considered the possibilities of patients 
carrying contagious diseases to the dental office, and other patients 
becoming infected from the germs of disease left in the plush dental 
chair, the carpets, curtains, and hangings about an operating room. 
There is also the more frequent and possible means of transmitting 
disease to be considered, the actual contact from instrumentation. 

It may not often occur in an ordinary practice that patients suffer- 
ing from a contagious disease apply for dental treatment, but it does 
often happen that patients apply while members of their family are 
suffering from a contagious disease. Such diseases as measles, 
diphtheria, whooping cough, scarlet fever, chicken pox and small pox 
are said to be capable of transmission by clothing. Then there are 
such diseases as tuberculosis, pneumonia, influenza and some pus 
infections which may be transmitted by an unkept office equipment. 
Disease may be transmitted through the water supply, the air supply 
or noxious gases. Even darkness is conducive to the growth of micro- 
organisms. 

To minimize as far as possible the transmission of contagious 
diseases in a dental office the operating room should have an abundance 
of direct sunlight, there should be no draperies or hangings about 
the room. The walls should be of hard finish and capable of being 
cleaned. The woodwork of plain finish, no crevices for the collection 
of dust. Cabinets, brackets and shelves should be plain and of hard 
finish. Drawers should not be lined with baize or fabric of any kind. 
The chair, and especially the head rest, should be covered with some 
material which is capable of being cleaned without destroying it. 
Plush is decidedly objectionable. The floors should be capable of 
being cleaned, as is the case with hard wood finish or linoleum put 
down in a whole piece and cemented at the edges so that water may 
not get under it. If a rug or cork is used to stand upon at the chair 
it can be cleaned frequently. Carpet in an operating room is the 
most unhygienic of all floor dressings. 

8 9 



QO ASEPSIS IN THE OPERATING ROOM. 

Typhoid fever and other intestinal infections are most frequently 
transmitted by the water supply. In some cities and towns the water 
is never fit to drink while in others it may be drunk if boiled and in 
others the water may be unfit for use only at certain periods. Water 
which is unfit to drink is unfit to wash a drinking glass or to rinse 
the mouth. 

The air supplied to an operating room is of some importance, 
especially to the operator, because he so constantly breathes it. Hot 
air heating often supplies air which is obtained from a dirty, damp 
basement or from sewer ventilators. Sewer gas often enters an oper- 
ating room from poorly trapped or ventilated plumbing. The fountain 
cuspidor is rarely trapped and is often the source of sewer gas. Coal 
gas leaking from defective pipes is an insidious kind of poisoning that 
an operator may not notice for months. The proper ventilation of an 
operating room deserves some consideration. 

The keeping of an operating room aseptic is no small under- 
taking. In fact it is well nigh impossible and yet it maybe kept clean 
enough so as not to be the means of spreading contagious diseases. 
Dust is the enemy of cleanliness and health. Every crevice, every 
crack, every shelf and every loose fabric is an element of danger. The 
walls, shelves, brackets, cabinet, chair, woodwork, light fixtures, 
windows, in fact every thing should be thoroughly cleaned once a week, 
with a brush, soap and water. After this the room may be closed up 
and formalin gas set free in sufficient quantity to fill it and allowed 
to remain for some hours. Formaldehyde tablets may be evaporated 
by heat over a Bunsen burner. Three or four tablets may be placed 
on a piece of flat metal over the gas flame. The heat necessary to 
evaporate the tablets is not very great. An equally efficient method 
is to place a couple of ounces of formaldehyde in a dish over the 
Bunsen flame which will quickly drive off the formalin gas. Once 
the gas begins to come off no one should remain in the room because 
the gas is very irritating to the air passages. The floors, chair, 
cabinet, bracket and all handles should be carefully cleaned and 
dusted with a damp cloth every day, and if there is any reason for 
suspecting that a patient has been in the office who was suffering 
from a contagious disease there should be general disinfection and 
ventilation. 

Such parts of the furniture and equipment as the operator is likely 
to handle in his ordinary duties should be wiped off with a cloth made 
damp by a five per cent solution of phenol or bichloride of mercury 
one to the thousand. There should be no waste cotton or dressings 



ASEPSIS IN THE OPERATING ROOM. 9 1 

permitted to fall upon the floor. There should be a convenient re- 
ceptacle for such things, that can be emptied frequently and sterilized. 
There is nothing much more unclean than the ordinary waste cotton 
holder where the plier points are drawn over the edges to remove 
the cotton, unless the holder is sterilized after each operation. Soiled 
towels, napkins and rubber dam should be immediately removed from 
the operating room. 

The dental cabinet should be thoroughly cleaned and wiped out 
with a damp cloth once a week and disinfected by the evaporation 
in it of formalin gas. Each tray and shelf containing operating instru- 
ments should be cleaned daily. Besides this the tray containing 
operating instruments should be covered with some material which 
can be easily removed and sterilized or destroyed. No instruments 
should be permitted in the cabinet until they are first sterilized. A 
fairly thick paper is quite suitable to cover the operating tray and may 
be removed after each patient and a new one placed in position. 
What are known as hygienic trays which are made of glass or granite 
are suitable and readily cleaned. 

The table on the bracket arm is often made of such materials and 
of such a form that it cannot be kept clean. A simple plain table of 
glass without any elaborate frame to hold it is all that is necessary. 
Once any decoration is attempted there are crevices for dust. With 
the swinging trays from the cabinet it is not necessary that the table 
should contain places for the operating instruments, medicine bottles, 
gold, amalgam and cement. TJie fact is the aseptic cabinet and 
bracket table and chair covering are not yet manufactured. They 
have not been demanded. The bracket table may be covered with 
a thick paper which can be removed after each operation and de- 
stroyed. 

The operator should be suitably dressed for the work he has to 
perform. His coat should be of washable material, close fitting 
around the neck and sleeves, no buttons or flats to catch in his patient's 
hair or clothing. 

Long hair and whiskers are not conducive to aseptic operations. 
The operator should aim to prevent his expired air from entering the 
patient's mouth or nostrils. This may be done by breathing through 
the mouth and by directing the exhalation either upward or downward 
by the position of the lower lip. If the lower lip be carried forward 
and upward the exhalation will be driven upwards while if the lip be 
held backward and under the upper lip the exhalations will be driven 
directly downwards. 



92 ASEPSIS IN THE OPERATING ROOM. 

The operators hands are almost impossible of disinfection; because 
though the surface may be sterile for a while it soon becomes infected 
from the natural exudations from the deeper parts of the skin. These 
exudations may be hindered for a time from pouring out by the applic- 
ation of astringents but the more the hands are used the more active 
the glands become. Those hands which are covered with a smooth, 
unabraded skin and have regular well kept finger nails can be made 
more aseptic than the dry, scaly hands with rough, irregular nails. 
Rough and violent scrubbing and scraping of the hands is likely to 
put them in such a condition that even this will not clean them. The 
nails are difficult to keep in condition unless trimmed short and 
kept smooth by files and brushes. Sharp instruments should not be 
passed under the nails to clean them because they scratch the tissue, 
leaving opportunity for lodgment of infections. Orange wood properly 
trimmed will serve to clean under the nails without wounding. The 
dentist should look upon his hands as one of his assets and should 
avoid everything that might in any way disfigure them or roughen the 
skin. The hands should be carefully washed in warm water and 
soap, the nails scrubbed thoroughly and cleaned beneath and again 
washed in running boiled water. This will suffice for ordinary cases, 
but if the hands have been exposed to pus infections or the saliva of 
the patient, or an operation is to be performed which demands the 
breaking of the mucous membrane or entering the circulation of the 
patient greater care must be exercised in cleaning the hands. They 
should be washed as above and then immersed in a one in forty phenol 
solution for three to five minutes or a two per cent solution of per- 
manganate of potash, or one in a thousand bichloride of mercury. 
Following this, alcohol may be poured over them. But if absolute 
certain asepsis is demanded rubber gloves should be worn. The 
general surgeon of today will not depend upon the disinfection of 
his hands, but wears gloves. There is no doubt that the dentist's 
greatest percaution should be to prevent the transmission of infection 
from one patient to another. While the patient may become infected 
from his own saliva the dangers are not so great as from infection 
from without. As the dentist operates for a patient his hands are 
certain to become infected from contact with the patient's lips, face, 
mouth or clothing, and should be cleaned and disinfected as parts of 
the operation are reached which demand aseptic conditions. The 
operator should avoid touching his clothing, his face, hair, or the 
furniture while treating roots of teeth or doing operations which may 
bring his instruments in contact with abraded surfaces. Before 



ASEPSIS IN THE OPERATING ROOM. 93 

cotton is wound on a broach for treating root canals the finger should 
be immersed in a bichloride solution or a formaldehyde solution. 

The field of operation should be as carefully prepared for operation 
as the hands or instruments. Patients often visit the dentist whose 
mouths are not even freed from particles of food from the last meal 
or two. It is well to have such patients rinse their mouths as thoroughly 
as they can with a two per cent solution of permanganate of potash 
before even a thorough examination is undertaken. A blast of air 
from a compressed air tank or a spray of one of the essential oils will 
clear an area for inspection. Not having these appliances a stream 
of tepid water forced between the teeth will clear out an interproximal 
space. Large cavities containing decomposed food and decalcified 
dentin should be opened and washed out with abundance of water. 
If the cavity is to be filled at once or the pulp involved the teeth in its 
vicinity should be dried and wiped with alcohol. And if the rubber be 
in position all of the exposed teeth should be thoroughly sopped with 
a strong disinfectant. Root canals should never be opened without 
thoroughly cleansing the cavity itself and the teeth about. 

The sterilization of instruments is perhaps more important than 
the sterilization of the hands or the field of operation because they more 
frequently come into contact with the secretions of the body. This 
is especially true of extracting forceps, lancets, clamps, separators, 
matrices, files, trimmers, scalers, broaches, explorers and hypodermic 
needles. Instruments should be selected with a view to their easy 
sterilization. Cone socket instruments and deeply knurled or wooden 
handles are not so easily sterilized as all steel and fairly smooth instru- 
ments. The dental hand-piece is difficult to sterilize without danger 
of rust or corrosion. 

There are two general methods of sterilization in common use, (1) 
by heat and, (2) by drugs. 

As a rule heat is more certain but even boiling for ten or fifteen 
minutes will not destroy the spores of some organisms. Sterilizers 
are most satisfactory which will permit of the water being drained 
off allowing the instruments to dry from their own heat. 

Sterilization by drugs is not always satisfactory because efficient 
drugs have to be used in such strength that unless the instruments are 
wiped dry before using there is a possibility of injuring the patient's 
mucous membranes. The odor and the time required for some drugs 
to act are serious objections. A 3 to 5 per cent solution of formalde- 
hyde will sterilize instruments in a shorter time than any other drug 
or combination of drugs which are at all suitable for the purpose. 



04 ASEPSIS IX THE OPERATING ROOM. 

Formaldehyde solutions will rust instruments rapidly but if borax 
be added rust does not occur. No dependence should be put in 
proprietary disinfectants for cither the mouth or instruments. Suffi- 
cient tests of the efficiency of these nostrums have been made to prove 
their uselessness. 

All the instruments used in an operation should be removed from 
the bracket table and washed in water and sterilized and then placed 
in their respective places in the cabinet. Such instruments as burs 
and serrated surfaces should be cleaned with a brush before being 
sterilized. The revolving brush wheel on the engine for cleaning 
burs is objectionable and should go with the cotton holder unless 
cleaned after each time it is used. After broaches are sterilized they 
should be kept in a closed drawer which is frequently sterilized with 
formalin vapor or in alcohol. 

The hypodermic needle may be pressed into a cork which tightly 
fits the bottom of a glass barrel about an inch in diameter and three 
or four inches in depth. The cork may be saturated with any steril- 
izing fluid which will not rust the needle. Such a needle is always 
ready for use. If the barrel be deep enough the whole syringe may 
be kept within it and covered with another cork. The nozzle of the 
water syringe should be kept in the formaldehyde solution when not 
in use. The nozzles of the spray bottles should be similarly sterilized. 

The sterilization of materials used by the dentist deserves some 
attention. Gold, amalgam, cement, and gutta-percha for fillings 
need little attention except where they are brought into contact with 
vital tissues. Gutta-percha is frequently brought into such contact 
but it is sterilized by heating before being used. The phosphoric 
acid and chloride of zinc prevent the carrying of infection by the 
ordinary cements. Gutta-percha points used to fill root canals are 
often inserted directly from an unclean drawer or box. They should 
be kept in alcohol in a wide mouth bottle well stopped. Cotton used 
for wipes should be sterilized by heat and kept covered as much of 
the time as possible. 

There are many minor operations performed by the dentist which 
are cared for in rather a slipshod method. Roots of teeth are ex- 
tracted about which purulent infections existed and no attempt made 
to wash out the cavity with any regard for asepsis. The water used 
and its containing vessel should be boiled, the syringe and the packing 
should be sterile. Every office should be equiped with sealed glass 
jars containing strips of boracic and plain gauze of different widths 
wound on a spool. Cotton wipes may be kept in a similar jar. The 






ASEPSIS IN THE OPERATING ROOM. 95 



jar and its contents may be sterilized in an oven or boiling water. 
The ordinary fruit sealer is an excellent jar for this purpose. With 
such an equipment the dental surgeon is always prepared for the 
management of the many surgical operations he is called upon to 
perform. 



CHAPTER V. 
HYGIENE OF THE MOUTH. 

BY GEORGE H. WRIGHT, D. M. D. 
ORAL HYGIENE OF THE INFANT. 

The highest physical development of the child is largely dependent 
upon its environment and its food. These two factors may be in- 
fluenced by the parent and oral hygienist. 

In order to have a clear understanding of the conditions necessary 
for a sound oral hygiene we must recognize what physiological proc- 
esses are concerned in the development of the oral cavity, the eruption 
of the teeth, and the possible changes which may follow any interference 
with its normal process and which may result in a distinct pathological 
manifestation. Heretofore, in dealing with the problem of oral hygiene, 
we have considered simply the adult, now we propose to take a view 
of the child at the beginning. 

Why do teeth erupt ? In our endeavor to answer this question we 
shall lay especial emphasis upon certain factors, as pulsation of force, 
constantly applied, that impels and moves the tooth onward out of 
its crypt and through the gum tissue. Any interference in this process 
induced by unnatural external causes, may so modify the direction of 
the eruption of these teeth as to cause not only reflex disturbances of 
digestion, with many other manifestations of pathological diseases, 
but may also modify the superstructure of the superior maxilla and 
cause decided malformations in all the facial bones, including the floor 
of the nasal fossa, the nasal septum, the antra, and may induce abnor- 
mal growths, thickenings of mucous membrane, such as adenoids and 
other obstructions that disturb normal functioning. 

Frequently the physician called in to attend a child who is dis- 
turbed in the process of teething, so called, will indiscriminately lance 
the gum, a fibrous tissue immediately over the erupting crown, and 
in that manner seek to give the child relief. He may succeed tempora- 
rily, because the arterial tension below the erupting tooth is relieved. 
The cusps of the tooth emerge through the wound and there is liber- 
ated into the oral cavity, a mass of liquefied alveolar bone and degen- 
erate connective tissue which normally is absorbed by the lymphatics. 
Only the crown of the tooth is formed at this time and is loosely held 

7 97 



OS HYGIENE OF THE MOUTH. 

within its alveolar crypt. The lancing relieves the tension which 
later subsides, and often the tooth returns to its former position below 
the gum; the cicatrix heals rapidly and histologically will exhibit a 
denser hbrous mass, considerably matted, and very resistant, and very 
difficult for the erupting tooth to cut through. At birth the crowns 
of all the temporary teeth are formed and any change in environment 
of a tooth may have an important influence upon the future lines of 
growth of the jaws and adjacent structures, for, coincident with the 
eruption, we have the development of the inferior meatus of the nose; 
at birth it is relatively unformed. The ma-xillary sinuses, sphenoidal 
and frontal, are post-natal developments. At birth the developing 
crowns of the permanent teeth occupy the position of the maxillary 
sinuses. The immediate result of this retarded eruption may be 
reflected in a decided deflection of the lines of growth, not only of the 
alveolar periosteum, but also of the adjacent bones. In the region 
of the intermaxillary bones, where the central incisors have been held 
for an abnormal length of time, the rest of the structure immediately 
above will suffer a corresponding retarded elongation. This may be 
observed in a later bending, or buckling, of the nasal septum, thereby 
closing on one side the nasal fossa, and on the other exhibiting a very 
wide opening. 

These deformities have their origin, during the period of and par- 
ticularly after the eruption of the first teeth; later the arch of the teeth, 
or substructure of the superior maxilla, loses some of its units of strength 
in supporting this structure, because the points of contact of the tem- 
porary teeth are unequal. Undue pressure is brought to bear at iso- 
lated points in closing the mouth, witn the reflex result that there will 
be distortion in the structure above. The permanent teeth which are 
developing immediately following the temporary teeth, continue this 
tendency to deformity, and the process may go on up to twelve years of 
age. In the meantime some enthusiast for early extraction may 
further complicate this deformity by the removal of some of these teeth 
mal-placed, and at this point we find one of our greatest complications 
as it leads to an abnormal, unhygienic condition of the mouth. Trian- 
gular spaces are formed into which are lodged accumulations of detritus 
difficult to remove, and in consequence there follows in its train most 
of the destruction of the teeth through caries, impaired digestion and 
imperfect respiration. 

We know that the crown of enamel with its interlining of dentin 
is formed first, and subsequently the dentin thickens and elongates; 

then it becomes covered with cementum and ultimately the root or 

• \ 

- 



ORAL HYGIENE OF THE INFANT. 99 

fang is developed with its covering of peridental membrane. But 
this completed growth is not a necessity for the eruption of the tooth, 
because we find upon dissection of the jaws, from six months up to six 
years, that the teeth erupt frequently without a vestige of a root, and, 
consequently, the disturbances within the oral cavity, and reflected in 
impaired digestion of the child — to be described in detail later — 
are not "due to the elongation of the root and consequent pressure upon 
the developing jaw," but to some other cause. 

This is fundamentally a problem for the specialist in oral hygiene, 
inasmuch as the mother of the child will frequently inquire of her den- 
tist, how soon she must "begin the care of baby's mouth." Fre- 
quently a child from four to six years will either through an accident 
lose the central temporary incisors, or loosen them by the habit of 
prying a pencil between the teeth; soon they are removed by the child, 
parent or dentist. At this period in the development of the per- 
manent central incisors (immediately following the temporary incisors) 
we find only the broad crown of enamel and no roots, and the crown 
situated high in the intermaxillary process. The too early loss of 
these temporary teeth from whatever cause may induce a thickening 
in the floor of the nasal fossa and malformation of adjacent structures, 
because the permanent central incisors are held by a new deposition 
of alveolar bone and a denser fibrous mass of gum tissue. Concurrent 
with the continued deposition of dentine and cementum at the apex 
of the tooth, the erupting force is reduced, because the apical region 
becomes more constricted, thereby reducing what is normally a wide 
area of vascular pulsating tissue which was the impelling force nec- 
essary for the eruption. These malformations become important factors 
in producing the subsequent pathological conditions within the mouth. 

The erupting tooth of a child slowly develops to the surface after 
absorption of the alveolar periosteal crypt, immediately above and ul- 
timately cuts its way through a fibrous mass of gum tissue. It is 
hastily assumed that all possible disturbance with that particular tooth 
has ended, but a few hours later, or the next day, the tooth may dis- 
appear below the gum into its crypt, leaving a small orifice capable of 
lodging decomposing food and myriads of bacteria. 

The fluctuating of the teeth in their coming and going shortly after 
their first appearance, is undoubtedly due to the change in arterial 
tension which is manifested through the large vascular pulp of each 
tooth. It is possible to record the pulsations of the heart, and count 
its beat through the freshly erupted tooth. The writer has made ob- 
servations during the past few years and watched this phenomenon. 



IOO HYGIENE OF THE MOUTH. 

Under normal conditions, the process of eruption is a natural and 
orderly physiological procedure on the part of nature. It is not our 
intention, nor within our province at this time, to go into details con- 
cerning the periods at which the groups of teeth erupt; that has been 
dealt with in another chapter. We shall consider, however, those as- 
pects which either directly or indirectly induce disturbances within the 
oral cavity, and which we are called upon to treat in order to establish 
a sound hygiene in the mouth. 

The mother invariably consults with her dentist upon the first 
occasion, after giving birth to her child. There have been excessive 
changes of metabolism, which have occurred during the period of 
gestation, and this is reflected quite markedly in the secretions, and 
particularly in the saliva and oral secretions, which becomes more acid, 
and in consequence exerts a deleterious influence on the teeth and ad- 
joining tissues. If the patient has been carefully instructed during the 
period of gestation as to the proper hygiene for the mouth, the evil 
effects upon the teeth, as a result of the changed metabolism, need not 
be fraught with so many evil results, as when entirely neglected and 
the debris naturally formed within the mouth is allowed to accumulate. 
Immediately preceding or at the time of the eruption of the teeth, 
there may be pathological complications within adjacent structures, 
as in the eye, ear, nose and throat. With this enormous structural 
upbuilding where nature is elaborating the materials for forty-eight 
teeth, and the jaws, there is much waste tissue to be disposed of. In 
close proximity to the erupting second lower molar there is a thick 
plate of alveolar bone. That bone and fibrous gum tissue in contact 
must be melted and absorbed before the tooth comes through. Some- 
times there w T ill be a swelling in the region of the submaxillary gland 
and lymphoid enlargements; intense pain, excessive salivation, fol- 
lowed by a hot and feverish condition of the oral mucous membrane. 
The disturbance may continue until we find an acute otitis media with 
a sinus and profuse suppurative discharge through the external ear. 
Usually within a few hours or two days at least, the offending molar 
will make its appearance through the gum, and disturbance will cease. 
So, too, in the region of the upper first and second temporary molars, 
we may find lymphatic enlargements involving the parotid, lachrymal 
gland and tonsil, with sinus and discharge through the lachrymal 
duct. The faucial tonsil and normal adenoid upon the side nearest 
to the erupting tooth may become considerably enlarged through the 
influence of the lymphatically absorbed waste tissue. Nature has 
undoubtedly developed and placed these lymphoid organs for a 



i 



ORAL HYGIENE OF THE INFANT. IOI 

useful purpose during this structural upbuilding. Wanton destruction 
or removal without adequate cause is to be deplored. 

If our observations regarding the arterial tension preceding and 
after the eruption of the tooth are correct, it is safe to assume that blood 
pressure has been a potent factor in the primary process of eruption, 
long before it has reached the surface through absorption of the walls 
of its bony crypt. If, during this early process before the appearance 
of the tooth, or the congestion of the fibrous gum, there should be from 
any cause whatever an undue arterial tension, then some of the dis- 
turbances noted in the young child may be accounted for, although 
there may be no external evidence of the teeth. 

There may be a feverish restlessness, periods of excessive salivation, 
desire of the child to bite its fingers, and rub its eyes and nose. There 
may be bright red areas in the region of the parotid and sublingual glands 
externally; possible rise in temperature with fretfulness and nervous 
irritability, and reflex disturbances of digestion with frequent ejec- 
tions of its food. The mucous membrane of the mouth, under these 
circumstances, may exhibit a hot and dry surface that lasts for a few 
hours to be followed by salivation. 

The etiology of these disturbances in the majority of cases may be 
referred to improper feeding, as indifferent formula for artificial foods, 
too much food, uncleanliness, or indiscriminate feeding. 

The child taking its nourishment at the breast obeys a natural 
instinct, and the mother's milk during the first months of feeding in- 
creases in quantity with the larger demands of the child, and analysis 
shows a decline in the nutritive proteids toward the end of the period of 
lactation. The child thrives best at the breast when the conditions 
are normal. When otherwise, then artificial feeding by formula is 
resorted to, but instead of a decrease in the quantity and proteid con- 
stituents of the food as observed in nature's method, we find the exact 
reverse, and the child suffers often in consequence of haphazard arti- 
ficial feeding; where the food values are progressively increased, while 
the naturally fed child is getting but a simple diet and that sparingly. 
It is not a question as to how much food the child shall take, but how 
little it should take in order to preserve the balance of perfect assimila- 
tion and growth. 

The salivary glands of the child are functionally active from four 
to six months and it is claimed that even in the youngest infant the 
chemical constituents of the saliva are capable of rendering soluble 
starchy foods; and some children have been known to digest and assimi- 
late starch during the earliest months, yet upon general principles it is 



\Q2 HYGIENE OF THE MOUTH. 



considered very unwise to introduce starchy food of any kind, because 
of the mechanical irritation and frequent inability to digest and as- 
similate them. 

The one great remedy for reflex disturbances of digestion, as a 
result of undue tension within the highly vascular tooth pulp, will 
be found in reduced and careful feeding, and the establishment of 
normal hygienic conditions. It may be necessary to starve the child 
for twenty-four hours before beginning where nature serves at the 
breast, in order to build up again. 

In describing the pathological aspect of the oral tissues in the child, 
the writer in the following has drawn largely from the admirable 
description found in Barrett's Pathology, Holt's Infancy and Child- 
hood, and Forchheimer. 

Stomatitis, in relation to disturbances or inflammation of the mucous 
membrane of the mouth and adjacent tissues, is in this sense restricted 
in its application; although the term is a broad one and could be applied 
to many diverse conditions. Stomatitis is common in infants, and is 
usually the handmaid of bad hygiene or unsanitary surroundings. 

This inflammation of the mucous membrane is frequently found 
where the child is artificially fed, instead of nursing at the breast. 
Either the proportion or formula for food is wrong, or there is not 
sufficient cleanliness and care in scalding the bottles and nipples, 
which will inhibit the growth of fermentative bacteria. The quality 
of the rubber in the nipple undergoes change, and under the influence of 
light and heat decomposes and becomes an active source of irritation 
to the tissues, which become poisoned. And even though these con- 
ditions do not exist as to improper feeding or unclean bottles, it is 
possible to develop a stomatitis on account of the accumulation of 
debris from remnants of food lodged within the orifices of erupting 
teeth, broken down epithelial cells, and combined products of inflamma- 
tion, which should be daily removed irrespective of the age of the child. 
Sometimes the most careful and conscientious nurse or mother will 
neglect this duty. 

A simple follicular stomatitis is an inflammation of the mouths of 
the mucous follicles. Small areas of the surface may be involved, and 
possibly induce degenerative changes as deep as the mucosa. The 
membrane will be flecked over with red points. As the inflammation 
spreads, more follicles become involved until the red points and patches 
merge, and the entire surface becomes turgid and tumid. As we look 
into the mouth, the tissues are hot, and dry, and red. There is con- 
siderable sensitiveness, and the child will shrink when examination 






ORAL HYGIENE OF THE INFANT. IO3 

is attempted. In the early stages, there will be excessive flowing of 
watery saliva due to the congestion of the blood vessels surrounding 
the glands, some febrile disturbance, bowels irregular, and either con- 
stipation or diarrhea predominating. Close examination reveals 
swelling of the muciparous follicles and possibly tiny cysts due to the 
accumulation of secretions within them. (Forchheimer.) The ad- 
jacent lymphatic glands become slightly enlarged and sensitive. 
Fortunately the constitutional symptoms with this form of stomatitis 
are not severe; there may be deranged digestion, vomiting, and a mild 
attack of diarrhea. The disease runs a brief course, and disturbances 
are usually easily corrected by care in feeding and cleanliness. 

In later stages, the degeneration spreads, the mouth becomes dry 
and parched, the blood vessels are congested and active nutrition is 
interrupted; then comes stasis or stoppage of circulation, and sloughing 
of the tissue commences. 

A child that is fed with a food that it cannot properly digest and as- 
similate will be poorly nourished, and as a result, almost any form of 
disturbance may ensue. The irritated condition of the digestive tract 
may produce diarrhea and gastric disturbances, and may result in 
ulcerative stomatitis. We have then an advanced stage of the first 
condition. The functions of the mucous follicles quite cease, and 
cracks and fissures open in the unlubricated tissue. All the preceding 
symptoms are aggravated. The child cannot take its food without 
difficulty, and what is ingested affords little nourishment because of 
the gastric disturbances that are always present. 

Aphthous stomatitis, or herpetic stomatitis as Holt calls it, is a 
form that may attack people of almost any age, and is characterized 
by some special appearances. Small round or oval ulcers appear 
upon the reddened mucous membrane of the lips, cheeks, tongue, or 
gums. They are from one to three lines in diameter, very little de- 
pressed, with a yellowish or white floor, and a red, narrow, perhaps 
slightly indurated, border. Sometimes two or more of them become 
confluent, thus forming an irregular, large ulcer. When these heal 
they leave no cicatrix. The aphthae do not spread like the spots in ul- 
cerative stomatitis, and they are distinctly painful, while the ulcers are 
not. 

Usually there is an increased flow of saliva accompanying them, 
the mouth is hot and feverish and the tongue heavily coated. Some- 
times the saliva excoriates the skin and the lips are thus kept con- 
stantly sore. The older ulcers may have the appearance of a diph- 
ther.tic membrane, being; a dirty gravish color. 



104 HYGIENE OF THE MOUTH. 

It is usually a self-limited disease and may cover a period from 5 
days to 2 weeks. There is a considerable doubt as to its etiology, but 
Holt* and Forchheimerf agree that it is of nervous origin, and not 
proved to be contagious. It is frequently associated with disturbances 
of the stomach and an attack may be coincident with the eruption of 
the teeth. 

Thrush is a form of stomatitis occurring in children and dependent 
upon the growth of a parasitic fungus. This consists of long, jointed 
threads, the saccharomyces albicans, which seem to belong to the family 
of the molds. Thrush is undoubtedly contagious. If a little of the 
exudate from the mouth is treated with a drop of liquor potassse and 
examined with the low-power of the microscope, the structure will 
reveal the fine threads (the mycelium) and the small oval spores. 
Slight catarrhal stomatitis, inadequate salivary secretions and lack 
of cleanliness in the mouth will favor its development. 

Wherever many young children are congregated, as in asylums, 
nurseries, and foundling homes, all are liable to contagion of the 
disease. It is most frequently developed in children suffering from 
malnutrition or other wasting diseases, or from any deformities within 
the oral cavity, as hare lip and cleft palate. On looking into the 
mouth of young infants a layer of thin white patches, almost a mem- 
brane, may be seen covering the palatal arch and appearing as white 
spots upon the tongue, while the mucous membrane about or at the 
borders of this coating seems to be in a healthy condition. The white 
flakes cannot be wiped or brushed off; any attempt to forcibly remove 
them will induce bleeding. 

The preceding remarks are more especially applicable to infantile 
stomatitis. The same or analogous conditions may be induced in 
adults by like causes. Anemic and poorly nourished persons are 
especially liable to inflammations of the oral tissues. The lips are 
dry and parched, and superficial fissures and cracks in the mucous 
membrane appear. In a less degree this will be observable upon the 
tongue, the buccal surfaces, and in the vault of the mouth. This 
may continue for some time, until finally, with the progression of a 
general febrile state, a more active stomatitis is developed that may re- 
sult in a local breaking down or ulceration. 

Neglect of the teeth and mouth tissues is a fruitful source of sto- 
matitis in adults. Food is left to ferment and putrefy, and the products 
of this action will be exceedingly irritative to the soft tissues, as well 

♦Infancy and Childhood: Holt, 247. 
t Archives of Pediatrics, ix, 330. 



ORAL HYGIENE OF THE INFANT. 105 

as destructive to the hard. There will always be gingivitis present in 
the mouths of those who do not give proper attention to the removal 
of foreign substances from about the teeth, and this, by continuity 
of tissues, may spread all over the mouth. Usually the action of the 
saliva upon the portions freely washed by it is sufficient to keep them 
clean and normal. But between and about the teeth, where food 
remains for an indefinite time, in the absence of proper care the gums 
are always irritated and more or less congested, and this may spread 
to adjoining tissue, with the result of an acute stomatitis in atonic 
conditions. 

In infantile affections the very first measures to be adopted nec- 
essarily imply an inquiry into the food and feeding. If the child is 
artificially fed, the nursing-bottle should be carefully inspected, and 
the food that is given must be scrutinized. If there is anything un- 
sanitary about either, it must be at once corrected. The rubber nipple 
must be sterilized, or, what is better, discarded and substituted by a 
new one that has been made thoroughly aseptic. If the child is poorly 
nourished through improper or insufficient food, that must be remedied, 
and plenty of nutritious matter that can be readily digested and assimil- 
ated should be given. If there are diarrheas or other wasting disor- 
ders, which will too often be the case, they must at once be attended to; 
it will be impossible to build up a patient while any process of waste 
is going on. All unhygienic surroundings must be remedied, and 
the patient should be given plenty of light and air, and proper exercise. 
In short, beneficent Mother Nature, upon whom we must finally rely 
for a cure, must be afforded every opportunity. Functional activity 
must be promoted, and all obstacles removed. 

After securing perfect sanitation the local treatment will be mainly 
depurative and stimulative. If a cathartic is indicated, two drams of 
castor oil may be administered. For the local irritation, a mouth 
wash consisting of a solution of five to ten grains of chlorate of potash 
to the ounce of water may be used as a mouth wash. If the child is too 
young to use this itself, a swab may be made by tying absorbent cotton 
to a stick of proper dimensions, and this may be used to apply the 
solution, employing a proper degree of friction. If the mouth is sore, 
it may be applied with a soft sterilized gauze — never use a soft tooth 
brush, it carries infection. The mouth may be occasionally washed 
out with the following preparation especially after eating: 

1$ — Borax, 30 grains. 

Sodium bicarbonate, 1 dram. 

Distilled water, 4 ounces. 



106 HYGIENE OF THE MOUTH. 

Or the following may be substituted in its place: 

R — Boric acid. 

Potassium chlorate, of each 15 grains. 

Lemon juice, ^ ounce. 

Glycerol, 6 drams. 

Never give syrups or honey to a child. 

If there are deep erosions of the mucous membrane, or ulcerative 
surfaces, it may be necessary to cauterize them, either with silver ni- 
trate, pure phenol, or chromic acid crystals. The last named are pref- 
erable in instances in which they can be conveniently used. The 
cauterized places should be subsequently dressed with a solution of 
calendula. 

The treatment of follicular, or ulcerative, stomatitis in adults does 
not materially differ from that in infants, except that more active meas- 
ures may be used. The remedies may be proportionately increased 
in strength, and personal care insisted upon. The teeth should be 
thoroughly cleansed, and all broken or sharp edges removed. A soft 
tooth brush should be employed after every meal, only when a normal 
condition has been established, and with it should be prescribed some 
antiseptic wash. A two per cent solution of zinc chloride may be 
used as a gargle. At night a spoonful of milk of magnesia should be 
taken into the mouth and rinsed about all the teeth, to be left upon 
them until the morning. Enough of good nourishing food should be 
given, and the patient should have plenty of pure air and sunshine. 

In cases of thrush in infants that are badly or insufficiently nourished, 
there is usually more or less of gastric or intestinal irritation in con- 
nection with the markedly atonic condition. This will probably 
require the administration of such correctives as rhubarb and soda, 
or lime-water. When the aphthae occur in older persons they are often 
spoken of as "canker spots," or "canker sore mouth." The usual 
treatment is roughly to cauterize the spots and dress them with a 
solution of calendula. If an active cauterant is not desirable, as in 
children, the aphthous patches may be repeatedly touched with the 
following solution: 

1} — Sodium salicylate, 1 dram. 

Distilled water, 6 drams. 

Or in place of the preceding this may be used 

T^ — Borax, 45 grains. 

Sodium salicylate, 75 " 

Tinct. myrrh, 1 dram. 

Distilled water, h ounce. 



DEPOSITS. 107 

The chlorate of potassium solution is strongly recommended. 

If the aphthae exist in considerable numbers, they may demand the 
use of antiseptic mouth washes. If they are the consequence of a general 
anemic condition, tonics and alteratives are of course indicated. While 
they are peculiarly uncomfortable, the aphthae have no serious patholog- 
ical signification, except as they are indicative of an atonic condition. 

DEPOSITS. 

Superficial deposits upon the teeth composed largely of inorganic 
precipitates have their origin from external sources, and most fre- 
quently are derived from the fluids of the mouth. In addition there 
are accumulations of organic detritus, as decomposing food, animal 
and vegetable; fermenting starches and sugars; advanced products of 
decomposition; waste and broken down epithelial cells from the mucous 
membrane, and myriads of benign and malignant micro-organisms. 
These combine to form a pasty and cheesy deposition, which is found 
about the cervical margins of the teeth and gums. This mass is not 
in the nature or form of a calcareous tartar, and is easily removed by 
the frequent and habitual use of the tooth brush and waxed dental 
floss. It is not always necessary to use a tooth powder every day, for 
once the teeth have been properly cleaned by the careful dentist, it be- 
comes comparatively easy for the patient to keep the mouth free from 
this debris. It must be emphatically stipulated, however, that these 
products of decomposition should be daily removed by the patient. 
In addition, if necessary, the dentist should insist upon seeing his 
patient at frequent intervals until there shall have been established con- 
ditions that indicate a normal, healthy mouth. 

No amount of filling and restoring of defective teeth will ever 
suffice to maintain a healthy mouth so much as the unremitting care 
and removal of these organic deposits. The elimination and pre- 
vention of caries is dependent upon the destruction of the micro- 
organisms of decay, and the removal of their acid products which are 
so destructive to enamel and dentin. The action of these organic 
deposits is not always readily appreciated. The destructive effects 
of the acid products in the interproximal spaces and angles formed by 
overlapping teeth, or where teeth have been extracted leaves the space 
to be filled in by the unsupported teeth, which causes a tipping for- 
ward thereby forming triangular pockets which lodge food and debris. 
The enamel may be quite thin at the points of contact in the interprox- 
imal space and universally so, yet not show an active break in the con- 
tinuity of the surface. This accounts for the apparent rapid destruc- 



IOS HYGIENE OF THE MOUTH. 

tion of the teeth, when in reality the destructive process has been going 
on for years. 

Green stains are among the simpler deposits found upon the teeth 
of young children as well as adults, particularly in the region of the 
cervical margins. These stains are wholly superficial and vary in 
color from a dark green or bronze to yellow. They are not indicative 
of any special pathological disturbance, only insofar as they denote 
an undesirable condition in the oral secretions. Their early removal 
is advocated, because they are claimed to be from a disease producing 
fungus which, if neglected and allowed to - remain, will penetrate the 
enamel, and so erode the surface as to form a series of granular pits 
which ultimately combine to form a distinct cavity. 

Erosions of the enamel surfaces frequently have their inception 
through the agency of the green stain deposits, and wherever there 
is a congenital weakness in the enamel, as in faulty structure of the 
enamel prisms, having soft white spots of calcification immediately 
adjacent to the interglobular spaces of the dentin, then erosion and 
decalcification and rapid destruction of tooth substance quickly follows 

Other stains found upon teeth are those deposits caused by the 
excessive use of tobacco and tea, and sometimes from the use of med- 
icines. Except from the unclean appearance produced by these latter 
stains, there appears to be no immediate injury to the enamel surfaces 
in consequence. It is important, however, that they should be re- 
moved; this may be done readily by touching the stained area with a 
small amount of tincture of iodine then scouring with English precip- 
itated chalk. If the surface is eroded and roughened, it must be 
dressed down smoothly with cuttle bone, or fine Arkansas stone and 
finally polished w T ith chalk. 

The salivary calculus, and the calcareous accumulations being 
deposited about the neck and roots of teeth, cause recession of the gum 
tissue and inflammation of the peridental membrane; these are among 
the most important of the deposits, because the neglected accumulations 
induce diseases of the gums and adjacent tissues, and although local 
and superficial in deposition may be the precursor of more serious 
disturbances. 

The salivary calculus is a deposit from the saliva. The calcium 
salts are held in solution through the agency of the carbon dioxide 
(C0 2 ) present in the newly elaborated saliva. This fluid is poured 
into the oral cavity where it encounters acids derived from a variety 
of sources, and is subjected to the action of the ferments from decom- 
posing foods. The quantities of saliva are more or less variable; 



CHEMICAL COMPOSITION OF SALIVA. 109 

this is also true of the calcic salts contained in it. The carbon dioxide 
(C0 2 ) is held in a very unstable solution, and upon exposure to the 
oxygen of the air and contact with the acids in the mouth, derived 
from various sources, the carbon dioxide (C0 2 ) is liberated, the calcic 
constituents lose their solubility, form precipitates upon the teeth, 
and give rise to what is commonly called salivary calculus or tartar. 
Combined with these calcium salts are products of organic decompo- 
sition, which cause the tartar to become a powerful irritant to the gum 
tissue, and induces inflammation in the contiguous tissues. 

The deposition of salivary calculus is mainly in the region of 
the mouths of the salivary ducts, as Wharton's duct and the duct of 
Steno. The greater amount is liable to accumulate upon the lingual 
surfaces of the lower incisors, and opposite Steno' s duct, upon the 
buccal surfaces of the upper molars. 

One of the predisposing factors in the accumulation of large pre- 
cipitates of tartar is found in the fungoid growths and deposits upon 
the teeth, made up largely of partially decomposed food and threads 
of the higher bacteria as the leptothrix or streptothrix actinomyces. 
The protoplasm of the filaments of these organisms breaks up into 
bacillus-like elements, and all combine to form an agglutinating mass, 
which holds the precipitates of calcium and becomes a nidus for a 
concretion. And although the mouth has been kept free from these 
organic bodies, it is possible to find a foundation for holding tartar 
deposits in the saliva itself, which is a mixed fluid derived from the 
secretions from the oral mucous, parotid, sublingual and submaxillary 
glands. These secretions are subject to considerable variation, both 
in physical as well as in chemical character. Ordinarily, saliva is a 
clear, viscid fluid, at times thin and watery and at other times thick 
and ropy. According to Michaels, it contains all the salts of the 
blood which are dialyzable through the salivary glands; this offers 
a fair index of the metabolic processes being carried on in the entire 
system. There are times when the viscid and tenacious quality of the 
saliva with its mucin constituents becomes dried upon the teeth, form- 
ing masses of sordes (Marshall) ; this, together with the debris of epi- 
thelial cells, mucous corpuscles and salivary corpuscles offers a favor- 
able nidus for tartar deposits. 

CHEMICAL COMPOSITION OF SALIVA. 

The chief constituents of a normal mixed saliva are ptyalin — 
a diastatic ferment — mucin, and the chlorides of sodium and potas- 
sium. In variable quantities traces of albumin, fat, potassium 



IIO HYGIENE OF THE MOUTH. 

sulphocyanide, sulphates and phosphates of the alkalies and alkaline 
salts, as the calcic phosphates, calcic carbonates and oxide of iron 
may be found; occasionally also traces may be found in normal saliva 
of urea and ammonium nitrate. "The source of origin of the saliva 
that contains these chemical constituents is from the blood, or more 
correctly from the plasma, which is filtered off from the circulating 
blood into the interstices of the glands, as of all living textures." 

In reaction the saliva when first secreted is slightly alkaline. Dur- 
ing fasting, although secreted alkaline, it soon becomes neutral. Tests 
of saliva with litmus paper frequently give an acid reaction, and this 
may be due to the elaboration of acids from foods, ferments and 
bacteria. 

Tomes gives the daily average of the amount of saliva excreted 
from 800 to 1500 grams, approximately from three pints to a little 
less than a quart. 

Lehmann has estimated the specific gravity of saliva in health as 
ranging from 1004 to 1006, and states also that there may be a rise as 
high as 1009 and a fall as low as 1002, without the evidence of any 
existing disease. 

Frerichs* gives the following chemical composition of mixed saliva: 

Water, 994. 10 

Solids* — 

Ptyalin 1.41 

Fat 0.07 

Epithelium and proteids (including serum -albumen, 

globulin, mucin, etc.), 2.13 

Salts:— 

Potassium sulphocyanate 1 
Sodium phosphate 
Calcium phosphate 

Magnesium phosphate f 

Sodium chloride 
Potassium chloride J 

5^_ 

1 ,000.00 

The excretion of the parotid gland contains slightly more water 
than the secretion from the submaxillary and sublingual glands, and 
in consequence is less viscid. It is rich in ptyalin, but contains no 
mucin; its calcic constituents are the carbonate and phosphate, the 
latter existing in minute quantities. According to Hoppe-Seyler the 
inorganic elements yield about 0.34 per cent.f 



*Kirkes' Handbook of Physiology, 1893, p. 295. 
t Marshall Op. Dentistry, 523. 



I 



SERUMAL DEPOSITS. Ill 

The secretions of the sublingual and submaxillary glands are poor 
in ptyalin but rich in mucin; the sublingual contains the highest per 
cent. Carbonate and phosphate of calcium yield about equal propor- 
tions. These elements amount to about 0.43 per cent in the sub- 
maxillary secretion, but the precentage is not so high in the sublingual. 

Mucin is derived largely from the mucous glands, and the organic 
and inorganic constituents average about 20 parts to 1,000. 

Berzeleus estimates the composition of salivary calculus as follows: 

Phosphates of calcium and magnesium 79.0 

Salivary mucus 12.5 

Ptyalin, 1.0, 

Animal matter soluble in HC1 7.5 

Calcic deposits from whatever source should be removed, and 
inflammations of the gums and mucous membrane of the mouth irre- 
spective of their origin must be relieved and resolved into healthy tissue. 
It does not necessarily follow that because we find large deposits of 
tartar upon the necks of the teeth that we have the disease of pyorrhea 
alveolaris. We have seen many patients whose teeth have been neg- 
lected, and who were innocent of the smallest effort on the part of a 
dentist in all their lives as to removal of the deposits, which were ex- 
cessive, and to whom the use of a tooth brush was unknown, yet upon 
the careful removal of these deposits and orderly and habitual use of 
the brush the mouth was quickly restored to a healthy condition. 

The deposits in some instances have been exceedingly thick, 
and upon the lingual surfaces of the lower anterior teeth an aggregation 
of successive layers has formed, that completely bound the teeth to- 
gether as in a plaster cast. The encroachment, however, does not 
always extend very far below the gum, nor necessarily involve de- 
struction of the peridental membrane. An early treatment of such 
conditions, to be described later, results in complete restoration with- 
out the accompaniment of the disease designated pyorrhea alveolaris. 

SERUMAL DEPOSITS. 

It is not the purpose of this part of our work to treat exhaustively 
the various authoritative opinions as to the etiology of the serumal 
deposits. We shall consider, however, a few of them in so far as to 
present a general summary that will guide us in recognizing these 
deposits which call for special treatment in their removal. The sub- 
ject has been considered more completely in the chapter on pyorrhea 
alveolaris. 



112 HYGIENE OF THE MOUTH. 

Dr. John Marshall,* in 1891, said, "That the deposition of the 
concretions upon the roots of the teeth in those localities not easily 
reached by the saliva, or in which the presence of the saliva would be 
an impossibility, is due to the causes which produce the chalky for- 
mations found in the joints and fibrous tissues of gouty and rheumatic 
individuals." 

Dr. G. V. Black has done considerable research work and has 
written an exhaustive paper, published in the American System 
./ of Dentistry, Vol. I, p. 953, wherein he speaks of a calcic inflammation 
; and phagedenic pericementitis as an accompaniment of the tartar de- 
posits upon the teeth in the region of the peridental membrane, and 
though he indicates his belief that the cause is wholly local, he also 
admits that a sanguinary deposit may be closely involved in its origin. 
He differentiates it as a destructive inflammation of the pericemental 
membrane, distinct from other inflammations of this tissue though 
possessing features in common with them. In summing up his esti- 
mate, he concludes that the disease is essentially one of the peridental 
membrane rather than of the alveolus, and the destruction of these 
two structures is so nearly synchronous that it becomes difficult to say 
which has gone first. 

Dr. C. N. Pierce f gives the name ptyalogenic calcic pericementitis 
to the conditions wherein the teeth are involved with calcic deposits, 
indicating, as he believes, the origin of these deposits and other calculi 
as traceable to the saliva. We are not concerned particularly in this 
section of our paper with the cause so much as in adequately recog- 
nizing the conditions in the mouth that call for treatment, and the es- 
tablishment of a sound oral hygiene. 

W. C. Barrett J has summarized the theory of E. C. Kirk on the 
formation of serumal calculus as follows: 

"The capacity of the blood stream for holding in solution the waste 
products of nitrogenous metabolism, the results of functional activity 
in the body, is determined by the alkalinity of the blood plasma. 
Any decrease in this diminishes its solvent power for these, and causes 
their precipitation in the tissues nourished by the blood stream. This 
lessened alkalinity may be general, affecting the whole sanguinary 
current, or it may be localized in certain tissues; in the latter case there 
will be a localized precipitation of the products of which uric acid is a 
type. Excessive work causes an increased blood supply to a part, 

* Transactions American Med. Assoc, 1891. 
t Am. Text Bk. Op. Dentistry, 2d Ed., p. 510. 
X Oral Pathology and Practice: Barrett, p. 139. 




SERUMAL DEPOSITS. 113 

and excessive oxidation and tissue waste, which in turn produce 
lessened alkalinity, or a tendency toward acidity. The ligamentous 
tissues are especially liable to conditions of this nature, and the peri- 
dental membrane, belonging to this category, is especially subject to 
affections of the character noted. Excessive work being put upon the 
investing membrane of any tooth, through malocclusion or by bad 
habits in mastication, by injuries from wedging, the application of 
ligatures, or other causes, the resulting hyperemia brings in its train 
overnutrition, localized diminished alkalinity, with the consequent 
deposition of urates." 

We have thus considered those superficial deposits found upon the 
teeth having their origin from organic debris and the saliva; it remains 
to briefly differentiate those which form upon the roots of the teeth 
primarily, and are commonly designated sanguinary calculus. Its 
characteiistic appearance is somewhat different from the salivary 
calculi, although these latter may, through a considerable period of 
successive depositions, become in time a dense, black, smooth supra- 
gingival deposit, having incorporated through the agency of pigmentary 
matter; oxides from amalgam fillings, and the action of medicines, 
which may cause it to assume the external color and appearance of 
the sanguinary calculus. 

The location of these depositis would indicate their entire indepen- 
dence in formation of the oral fluids, as they are found precipitated 
upon the periphery of a root that is not denuded when formed, and 
where there is no destruction of the gingival border. It is distinctly 
more irritating to the tissues than the smooth amorphous deposits from 
the salivary calculus, and this may be due to its position within the 
alveolar socket where it is preeminently a foreign body. The deposi- 
tions are not in uniform amorphous masses, but as separate minute 
nodules, which cling tenaciously and are with considerable difficulty 
removed. Successive aggregations unite to form a mass that is hard 
and brittle, whose color is olive black or olive green. It is unlike 
the salivary calculus which may be readily detected, and is therefore 
easy of diagnosis, as it is hidden away within the socket, sometimes 
beyond a point of accessibility for its removal. 

The removal of deposits, whether of salivary or serumal origin, 
demands the highest skill and care in the use of specially designed 
instruments for this operation. No hurried and indifferent service 
rendered the patient will ever restore the oral tissues to a normal con- 
dition; this result is obtained only by deliberate painstaking care, 
combined with intelligent work. 



114 HYGIENE OF THE MOUTH. 

The selection of proper instruments must be determined not by 
any arbitrary rule, but according to the requirements of the operation 
to be performed, and the writer has obtained the best results from a 
composite set selected from the admirable instruments designed by 
Doctors Kirk, Darby-Perry, King, Marshall, Abbott, Harlan, Smith, 
S. S. White Manufacturing Company, and J. W. Ivory. 

The instruments should be clean and sterilized, and everything 
about them suggestive of care. The patient should be comfortably 
seated, and the chair inclined and head-rest adjusted in order to have 
the mouth receive the largest amount of light possible. All napkins, 
large or small, must be fresh and clean. The larger napkin should 
be sufficient to protect the patient's clothing from flying particles and 
loose debris. Ordinarily the operator stands firmly on the right side 
of the patient with his left arm around the head-rest, and by this 
means is in a position to gently steady the head. Small rectangular 
pieces of sterilized gauze from 4x4 inches to 5 x 5 inches are most use- 
ful in receiving the soft deposits as they are spooned off. A small piece 
of gauze should be rolled and placed between the lower lip and gums 
to prevent pressing the septic matter into the delicate membrane of 
the lips. The lips may become infected and considerable swelling 
be induced by lack of care on the part of the operator. In order to 
lessen this liability it may be necessary to prescribe a suitable mouth 
wash and special application of the tooth brush for a few days preced- 
ing the operation of removing, the debris. Where conditions are ab- 
normal, this precautionary treatment is of value in preventing further 
inflammation. 

The left hand should hold the mouth mirror, which serves the 
double function as a tongue depressor and light reflector. The eye 
of the operator should always follow the scaling edges of the instrument 
as near as possible, and whether the movement is a drawing upward or 
pushing downward, the scaler should be so held and supported by the 
fourth and fifth fingers resting upon the adjacent teeth, that there 
shall be no danger of a slipping and plunging into the tissues of the 
gums. When a deposit has been definitely located and dislodged, 
it should be immediately removed and accounted for. It may be 
necessary to frequently syringe the tooth and membranes with a warm, 
antiseptic mouth wash in order to facilitate the complete elimination 
of all foreign irritants. 

Whenever there are indicated deposits below the gingival margin, 
it is well first to remove carefully the superficial deposits upon the sur- 
faces of the teeth above the membranous tissues; beginning at th 



. 



SERUMAL DEPOSITS. 115 

central incisors and cautiously working round the arch to the third 
molars; each half of the mouth being treated successively until all 
the teeth have been scaled. The time necessary for this operation 
will depend somewhat upon the conditions presented, and it may be 
necessary to resume the operation at a future time. During this pre- 
liminary scaling, mental note should be made of the pockets formed 
between the roots where debris and calcic deposits accumulate; minute 
congestion of the gingiva; triangular spaces and irregularities as a 
result of inclined crowns, and any other factors predisposing and 
favorable to the accumulation of deposits, as cavities through caries; 
furrows between the cervical enamel and cementum; hypertrophied 
tissues; eroded cement fillings; rough and pitted gold fillings and sur- 
faces; projecting amalgam and other fillings; improperly fitting clasps, 
artificial dentures and gold crowns. All supragingival surfaces should 
be most scrupulously scaled, cleaned and polished as a preliminary 
operation to further removal of the subgingival accumulations. It 
matters not who may be responsible for the old restorations, it is a 
necessity that the roughened fillings and surfaces be cleaned and 
polished. 

Incidentally, the patient's attention may be directed to certain 
localities within the mouth where there is a special tendency for the 
retention of decomposing foods. 

Subgingival deposits invariably induce distinct pathological con- 
ditions within adjacent membranes, and each tooth carrying upon its 
surfaces and roots these foreign bodies should be treated individually, 
until all trace and evidence of their presence has been removed. 

The tenacity with which serumal deposits cling may call for the 
use of a softening agent, and a twenty per cent aqueous solution up to 
fifty per cent of trichloracetic acid may be used with beneficial results. 
The percentage strength of the acid necessary is to be determined by 
trial. The acid is carried into the region of the deposit, either upon a 
wedge-shaped piece of orange wood stick or upon a few fibers of cotton 
soaked in the acid. A gentle pumping motion will suffice to reach the 
nodular deposits. Lactic acid has been recommended for the same 
purpose with claims for its therapeutic value. 

The chiseling and scaling and applications of the acid may be re- 
peated until all the nodules are removed, and the roots are clean and 
smooth. Care must be exercised not to lacerate the tissue of the gums 
and peridental membrane. The force employed should be well under 
the control of the operator to avoid destruction of the cementum, and 
unnecessary loosening of the tooth. Too much movement of the tooth 



Il6 HYGIENE OF THE MOUTH. 

within the alveolar socket is liable to carry granules of calcific deposits 
and septic matter further into the pocket and tissues. Should the 
teeth be very loose, a temporary supporting splint, made of softened 
modeling compound, and applied to the labial surfaces of the teeth en 
masse, when the lingual surfaces are under treatment, w T ill be an effective 
and agreeable support; the reverse application when the labial surfaces 
are treated. Frequent syringing with a warm antiseptic mouth wash, 
such as^phenol sodique or peroxide of hydrogen (H 2 2 ) three per 
cent solution, to remove debris is necessary. 

The author counsels against a too early application of massaging 
of the gum tissues, because of the danger of incorporating within the 
tissue loose deposits that become a continual source of irritation. This 
operation may be deferred until later when all trace of inflammation 
has disappeared, and careful exploring reveals no deposits. 

Ultimately, a weak solution of zinc chloride may be worked into 
the pockets as a stimulating astringent. New vitality may be induced, 
bringing new granulations to the alveolar edges by scraping with a 
bur or hoe excavator. 

The treatment should end when all is clean, and there is an effusion 
of coagulable lymph, which should be left and not washed or wiped out, 
because at this point nature can accomplish much in the restorative 
process. 

The dentist should determine for his patient how soon this op- 
eration should be repeated, and that will be governed by keeping a 
careful record of the status of the case with treatment and results for 
future reference. 



CHAPTER VI. 
DENTAL CARIES. 

BY C. N. JOHNSON, M. A., L. D. S., D. D. S. 

In a work like the present it is deemed unnecessary to go minutely 
into the pathology of this disease and yet it is well to consider some- 
what carefully certain of the etiological factors which affect us vitally 
in operative dentistry. Every operator who attempts to save the 
natural teeth should have a reasonably clear conception of the cause 
or causes of caries, of its modus operandi, and the peculiar methods 
of its attacks. If he is thoroughly informed on these points he will 
be in a position to do better work thereby, and recognizing this the 
foremost men in the profession have always sought to inform them- 
selves in regard to these matters. 

Some of the theories of the past have been so wide of the mark 
that they are interesting only as milestones along the uphill road of 
scientific progress, while others, though crude and lacking in demon- 
strated data, are worthy of the greatest respect in the light of the most 
recent knowledge. Certain writers have held the theory that inflam- 
mation played a part in the breaking down of the tooth tissue, that the 
character of the tooth structure itself was the most significant thing 
connected with it, and that the disease progressed from within outward. 
Others thought that while the disease began upon the surface of the 
tooth and progressed inwardly it was due chiefly to the chemical 
reaction of the saliva, that in fact it was acid saliva which produced 
the decay. But it was inconceivable to think that the saliva ever 
became sufficiently acid to eat into a tooth in the manner in which we 
find caries progressing, or that the soft tissues could tolerate it if it 
did. Not only this but if the saliva did the work we would find the 
teeth attacked uniformly upon all surfaces bathed in saliva while 
as a clinical fact there are certain surfaces in which decay seldom 
or never has its initial point of entrance. Some of our close observers 
noted these things and away back as far as 1828 Robertson indicated 
that the carious process was due to the action of some agency occurring 
immediately at certain points where cavities were to begin, his idea 
being that it was caused by "decomposition." This theory was of 
course vague as to the real active agent of caries, but it was correct 

117 



1 [8 DENTAL CARIES. 

in the principle that it was localized at certain points and was not 
general in the fluids of the mouth. There was much conjecture about 
the whole question of the active agent of caries till Professor W. D. 
Miller demonstrated in 1884, that it was due to the formation of acid 
brought about by micro-organic growth in the mouth. The findings 
of Miller have stood the test of investigation since then, and while 
there are many factors in the development of this disease which we 
do not yet quite understand, still they gave us the first real basis of 
scientific knowledge to work from. 

In a somewhat close clinical observation of the behavior of caries, 
the variation in its manner of attack, and in its general modus operandi 
in different cases, it is hard to conceive that it is always brought about 
in the same way or that its progress is invariably governed by the same 
conditions. That an acid causes the solution of the tooth tissue seems 
settled, and that this acid is the product of micro-organisms is also an 
apparently accepted fact. But why is it that we find such a variation 
in the manifestations of the disease in different mouths, and even in 
different periods in the same mouth ? We may find micro-organisms 
in all mouths — in fact the very micro-organism which Miller demon- 
strated would bring about decay, and decay which could not be dis- 
tinguished from that occurring in teeth in the mouth— and yet there are 
some mouths in which decay never occurs, and in most mouths where 
it does occur there is a great variation in its virulency at different times. 

It was formerly the prevalent idea that these variations were due 
to differences in the tooth structure, that one tooth was harder than 
another and would therefore withstand the attack of the carious agent 
better, and this impression was so strong in the profession that it 
finally communicated itself to the laity and is still firmly fixed in their 
minds. It is common to hear patients say that their teeth are so soft 
that it is almost impossible to save them, or on the other hand that 
they are growing harder so that they do not have so much trouble 
with them as formerly. This has been a most difficult fallacy to 
dislodge from the minds of the profession, and it has been the means 
of the loss of a very great number of teeth which otherwise might have 
been saved. The impression that the teeth are inherently so defective 
in structure that they are thereby peculiarly susceptible to the attack 
of caries is very disheartening, and it has led many patients to abandon 
any effort to save them and to allow them to go by default. This 
impression has too frequently been fostered by members of the pro- 
fession, whose function as teachers of the public should have made 
them guard against such false and harmful doctrine. 



1 



DENTAL CARIES. II9 

It is now more than ten years since the investigations of Dr. G. V. 
Black demonstrated conclusively that there is really little variation 
in the chemical constituents of the teeth of different individuals, and 
that what variation there is has little or nothing to do with the inception 
of dental caries. This came as almost a revolutionary statement 
at the time but his findings have never been disproved. Neither do 
the teeth of individuals grow harder and softer in any such sense as 
would account for the variations we 'see in the same mouth in the 
tendency to decay at different periods. Teeth grow r slightly harder 
as age advances but this change is exceedingly slow and not of a 
character to affect the manifestations of caries. This is readily under- 
stood when we recall the fact that the teeth are the most stable organs 
of the human body, and are not being constantly torn down and built 
up by waste and repair as are other tissues. 

And yet the impression in the profession that some teeth were 
very much harder than others was a perfectly natural one, owing to 
the difference in behavior of teeth under cutting instruments. This 
difference could not escape the attention of the most careless observer. 
Some teeth crumble away under chisels, excavators and burs, as if 
composed mostly of chalk; while others resist the attack of steel instru- 
ments almost to the point of striking fire. This led to the impression 
of varying softness and hardness in the teeth, and quite naturally to 
the conviction that this had a direct bearing on the tendency to decay. 
But there is another reason to account for the difference in behavior 
of teeth under instrumentation, and it is in accordance with close 
clinical observation that these same so-called "soft" teeth sometimes 
remain in the mouth for life free from caries while the "hard" teeth 
as frequently decay. It simply resolves itself down to a question of 
environment — the conditions which surround the teeth — rather than 
to the organic structure or constituents of the teeth themselves. 

The reason that teeth vary in their resistance to cutting instru- 
ments is limited almost wholly to the enamel and is due chiefly to the 
arrangement of the enamel rods. In some teeth the rods stand nearly 
parallel and radiate outward in regular order from the dentin in a 
comparatively straight line. It is noteworthy that in any enamel 
the cement-substance which holds the rods together is not very strong 
and the enamel is easily cleaved in line with the rods. It will thus be 
seen that straight-grained enamel like this will break down readily 
under instruments. But there is other enamel in which the rods 
pursue a wavy course, and a section of w r hich looks something like 
the structure of a gnarled oak. When a chisel is directed against 



120 DENTAL CARIES. 

such enamel as this it meets the stout lateral resistance of the rods 
themselves and is broken down with exceeding difficulty. 

But there is no enamel formed in the mouth of man which the acid 
of decay is not capable of dissolving if the conditions are favorable 
to its development, and so all enamel is alike subject to the attack of 
caries. This one difference may be noted that when decay has once 
begun it is reasonable to suppose that it will progress more rapidly in 
enamel where the rods stand straight so that the acid can have ready 
entrance between them than it will in wavy enamel where the access 
is less easy, though this has no relation to the question of the liability 
of the teeth to the original inception of caries. 

If, then, it is a matter of the conditions surrounding the teeth which 
chiefly influences this disease, it is imperative that we study these 
conditions somewhat carefully, and herein, be it said, lies the future 
hope of the profession in controlling and ultimately in preventing a 
disease which is acknowledged as being the most prevalent of all 
diseases of the human race. Had it been a question of the tooth 
structure there would have been small hope because we have learned 
that when once developed we cannot change that, but being a question 
of condition we may reasonably expect in time to so control the sur- 
rounding condition as to limit the disease. 

First it is necessary to learn what the conditions are which influence 
the inception of decay. We have said that the micro-organism of 
caries may be found in all mouths; then the natural query is, why do 
we not find decay in all mouths ? What is the particular agency which 
makes it possible for the micro-organism to bring about caries in one 
case, and impossible in another? Dr. J. Leon Williams, and Dr. G. 
V. Black have called attention to what they consider an important 
factor in the institution of caries, viz., the formation of gelatinous 
plaques on the surfaces of the teeth. We know that there are certain 
micro-organisms which in the process of their development produce 
a material closely allied in appearance to gelatin, and these are called 
gelatin-forming micro-organisms. The micro-organism of caries is 
one of this class, and it is the opinion of W T illiams and Black that it is 
mainly through the agency of these plaques that cavities are formed. 

It is of course known that an acid in order to dissolve enamel in 
the way we see it in the mouth must be a strong acid, and unless the 
micro-organisms have some protection to work under their acid would 
be diluted very quickly in the fluids of the mouth, and thus their 
destructive process be interfered with. It is therefore the idea of these 
investigators that it is by virtue of the protection given thei micro- 



, 



DENTAL CARIES. 121 

organisms through the formation of gelatinous plaques that the begin- 
nings of decay are brought about. A film is formed on the surface 
of the enamel and under cover of this the micro-organism may produce 
its acid in concentrated form and attack the enamel undisturbed by 
external interference. In fact Dr. Williams has been able to make 
ground sections of teeth thin enough for microscopical examination, 
showing the film in place with the micro-organisms under it and decay 
beginning in the enamel. Of course, after a cavity has once been started 
the micro-organisms have a sheltered place in which to work and do 
not need this gelatinous protection, but it is in the inception of caries 
that it plays an important role. This film is not soluble in the fluids 
of the mouth nor is it easily dislodged when firmly attached. No 
rinsing of the mouth with liquid will affect it, and it takes appre- 
ciable friction with a tooth brush to dislodge it. The saliva may 
therefore flow freely over its surface without disturbing it, and even 
the most potent of the mouth washes yet devised will not dissolve it. 

In this view of the case it is concluded that the significant thing 
in dental caries is the formation of this film, and that it is really the 
controlling factor in the question of immunity and susceptibility. 
In some mouths the conditions seem favorable for the production of 
these plaques, in others not, and upon this the issue is turned. In 
referring to plaques it must be remembered that a distinction should 
be made between these gelatinous plaques and patches of inspissated 
mucus and greasy masses of material left adherent to the surface of 
enamel through neglect in caring for the teeth. 

Dr. W. D. Miller in writing on this subject seems to place less 
significance on the film than Williams and Black, and claims that the 
case is not yet proven. He says that we may find these films freely 
in mouths where there is no decay, and that we may also find cavities 
without the presence of a film. In the latter instance he admits that 
the absence of a film after a cavity has started is no evidence that it 
may not have been there in the beginning. 

In point of fact we have had just sufficient knowledge on this sub- 
ject to make it imperative that we have more. As has already been 
intimated the behavior of some cavities is so entirely different from 
that of others that it is hard to conceive that they are all influenced 
by the same factors, and it is hoped that further investigations 
along these lines will give us a broader view of the whole question, 
and clear up some of the points which at present seem somewhat 
clouded. 

But what concerns us most at this time are the clinical manifes- 



[22 DENTAL CARIES. 

tat ions of immunity and susceptibility as we meet them in our every 
day practice. Dr. Michaels of Paris in studying the manifestations 
of susceptibility and immunity, took the ground that they were largely 
influenced by the condition of the fluids of the mouth, and claimed 
that in all cases of high susceptibility to dental caries there was a 
superabundance of ammonium salts in the saliva and an absence of 
sulpho-cyanates, while in immune mouths there was a diminution or 
an absence of ammonium salts with the presence of sulpho-cyanates. 
More recently Dr. F. W. Low of Buffalo, N. Y. has practically con- 
firmed Michaels' findings, and goes one step further in an effort to 
control the tendency to caries. In cases of great susceptibility he 
has been administering the sulpho-cyanates to patients with what 
seems to promise success in arresting the tendency to decay. It is 
hoped that these investigations will lead to something definite in the 
way of controlling this disease. A close observation of the phenomena 
of caries in the average susceptible mouth will disclose the fact that 
there are certain times when the disease is much more active than 
others. The periodicity of dental caries may be studied with much 
profit by the dentist, with the result that he is better equipped to 
manage the cases that come to him and more encouraged to persevere 
in the face of an apparently hopeless condition where the active agent 
of caries seems to be running rampant over the entire number of teeth 
in a given mouth. 

It is very rare indeed where the progress of this disease goes on 
uninterruptedly to the destruction of all the teeth in a mouth even 
when no attempt is made to arrest it, and much rarer in the event of 
any effort being put forth on the part of the dentist and the patient 
toward its control. That this is true is sufficiently evident from the 
large number of cases seen in practice where some of the teeth have 
been lost many years previously while the rest are being preserved 
with very little tendency to decay. The lesson of this is that if we can 
carry a case through a period of great liability to decay we may reason- 
ably expect a period of immunity to come sooner or later and with 
this to aid us in our efforts we may confidently hope to save the teeth 
for a lifetime so far at least as decay is concerned. 

One very significant fact in this connection is worthy of especial 
note — a fact embodying the greatest encouragement and carrying 
with it the highest incentive to persistent and painstaking effort on 
the part of the dentist. This is the assurance, established by a very 
close clinical observation in the study of cases extending over many 
years, that the period of immunity may be advanced very materially 



i 



DENTAL CARIES. 1 23 

by proper dental service at the time of greatest susceptibility. In 
other words when a dentist is struggling with a. discouraging case of 
caries, endeavoring to keep the teeth free from deposits and insisting 
that the patient does his part in this work, when he is filling cavities 
which develop with disheartening frequency and repairing fillings 
that have failed, he may be assured that the result of his efforts does 
not stop with the teeth he is operating on, but that in his attempt 
to suppress decay he is changing the conditions in this mouth and 
establishing a state of immunity which will eventually aid him materi- 
ally in saving the teeth of his patient. With this view of the case no 
dentist should lightly yield up decaying teeth to the forceps, nor should 
he become discouraged however prevalent decay may be in the mouth. 
There are exceptions to all rules in practice, and there are some mouths 
in which the tendency to caries seems to persist for a disheartening 
length of time, but in the average case the results are so very gratifying 
that it is well worth the effort of both operator and patient to follow 
up a line of treatment tending to its suppression. 

The period of greatest susceptibility to dental caries is in youth, 
and it is here that our best endeavor in controlling decay should be 
put forth. If we can successfully save the teeth to the twenty-fifth 
year the worst of the difficulty is over, except that in mouths where 
there has been great susceptibility we may look for occasional relapses 
even where a condition of comparative immunity has been established. 
The circumstances which bring about these relapses are not always 
apparent and it is sometimes difficult to account for them. Anything 
which changes the conditions of the mouth may do it, such as a pro- 
tracted illness, a change of climate which involves an entirely new 
environment, or any radical difference in the mode of life, or dis- 
turbance of the functional equilibrium of the individual. But usually 
if a relapse comes it is easily controlled and not nearly so severe as the 
original attack. 

This reference to the original attack, the relapses, and the periods 
of immunity does not imply that there is a sharp line of demarcation 
between them. An occasional cavity, or cavities, may develop at 
any time, but there is a very great difference between this and the 
awful havoc which we see so often occurring during periods of great 
susceptibility. Neither does it follow, when we get a set of teeth in 
good condition after susceptibility, that there will be no further need 
of dental service, even though the mouth should remain immune. 
Where decay has once manifested itself extensively in a mouth the 
teeth should have the supervision of a dentist at regular intervals 



124 DENTAL CARIES. 

afterward. There is always the necessity for hygienic treatment 
in the way of removing deposits and general prophylaxis, besides the 
repairs so frequently required in the operations performed during 
susceptibility. In a delicate child during the growing period if the 
teeth decay rapidly it is not always possible to do permanent w r ork, 
and we may carry the teeth to the twentieth or even twenty-fifth year 
and have the formation of new cavities practically stopped, but with 
the necessity before us of making more permanent operations as the 
other ones fail from time to time. It is always best, of course, to make 
permanent operations in the beginning if -this is possible, but it is 
not always possible with some of the temperamental conditions we 
meet in practice. 

To carry one of these young mouths through the susceptible period 
is often very trying but the result is well worth the effort. The plan 
of procedure should be about as follows: When a child is brought 
to the dentist with the teeth decaying rapidly there should be no half- 
hearted measures or perfunctory attention to the work. It is not 
merely a matter of filling cavities, though this of course should be done 
at once, and done as thoroughly as the circumstances will permit. 
But what is of equal consequence is that a campaign of prophylaxis 
be instituted with the definite aim of limiting the disease as far as 
possible in the future. The child should be schooled into a system 
of caring for the teeth by such an impressive lesson from the dentist 
that it cannot well go unheeded, and there should be a regular inspec- 
tion of the teeth by the practitioner to see that proper care is being 
given them, and that normal function is maintained. The key-note 
to the whole situation is the alteration of existing conditions in the 
mouth, and while — as has already been intimated — we do not know 
all we should about the conditions which influence this disease, yet 
we are certain of one thing that the establishment of full functional 
activity is favorable to the limitation of the disease. To this end all 
teeth should be kept comfortable for mastication, and w r herever we 
find evidences that mastication is not being properly performed we 
should discover the cause and remedy it. A close observer can always 
tell whether or not the teeth and gums are subjected to the amount 
of friction necessary for perfect mastication by noting the unpolished 
surfaces of the teeth and the hypertrophied and congested condition 
of the gums, and where it seems impossible to establish the habit of 
good mastication in any given case, or in any particular region of a 
mouth, the child should be instructed to make up the deficiency by 
friction of the brush for a stated period of time each day. The time 



A 



DENTAL CARIES. 1 25 

should be set by the dentist, and the patient urged to brush by the 
watch. The friction of the brush moistened in cold water over the 
teeth and gums for three consecutive minutes twice a day will soon 
have a very appreciable effect in stimulating the tissues to healthy 
action, and in polishing the enamel smooth and bright. 

Cavities should be filled as fast as they occur, the aim being to 
keep caries out of the mouth at all hazards. Sometimes the disease 
is so rampant that it is difficult to maintain the courage of the patient, 
and yet such a case should be fought with all the energy and enthusiasm 
of the operator, to the end that he inspires the patient with the con- 
fidence of ultimate success. Such patients should be carefully schooled 
in the theory of an approaching immunity, and the operator who is 
in earnest in his management of the case may conscientiously promise 
this on the basis of what has been observed in a close clinical study 
of such cases. There is a reasonable expectancy that in ninety-nine 
cases out of one hundred the teeth can be saved if proper attention is 
given them, and the usual history is that even in a very susceptible 
mouth about the eighteenth or twentieth year the conditions begin to 
clear up and the hardest part of the contest is over. 

It is true that teeth are sometimes neglected so that when the dentist 
is finally consulted — usually as the result of pain — the conditions are 
so bad as to be very discouraging, and yet there is no case so hopeless 
where sufficient of the tooth is left as a basis for a filling, inlay or 
crown that the dentist should let it go by default. It is the lack of an 
enthusiastic application on the part of the dentist, a failure to show 
forth an evident confidence in the possibility of saving the natural 
teeth, and the neglect to sufficiently emphasize the importance of 
retaining them that has led many patients both in youth and middle 
life to become unappreciative of their real value, and indifferent as to 
their care. 

The dentist may not be able as has already been intimated with 
our present knowledge to treat the mouth medicinally so as to change 
a susceptible case to one of immunity, but he assuredly can by insti- 
tuting the proper line of prophylactic and operative procedures so 
influence the conditions as to at least control the disease and ultimately 
save the teeth. Not only this but he can by pursuing the proper course 
in the management of these cases so advance the period of immunity 
from generation to generation as eventually to limit the disease and 
bring it under easy control. It is frequently noted now that even 
where the deciduous teeth are extensively affected, if proper attention 
is given to the case the conditions are so changed that there is little 



120 DENTAL CARIES. 

tendency to decay of the permanent teeth, and they may be saved 
without much demand for filling. 

The future hope of the profession is in the study of conditions 
which exist in the mouth, and while the ability to properly perform 
operations is exceedingly important it is not more so than a close 
observation of the phenomena which influence disease and also which 
affect materially the outcome of our technical procedures. If we 
understand conditions we shall operate more skillfully, more intel- 
ligently, and the result of our work will redound to the greater credit 
of the profession and a more lasting benefit to those who place them- 
selves under our care. 



CHAPTER VII. 

EXAMINATION OF TEETH FOR THE FINDING OF 
CARIOUS CAVITIES. 

BY GARRETT NEWKIRK, M. D. 

The practice of medicine in all of its departments may be com- 
prehended in two great divisions: First, diagnosis — finding out what 
is the matter; second, the choice and application of remedies. 

Physical exploration of the teeth for the discovery of caries might 
be styled mechanical diagnosis. It should be as carefully and thor- 
oughly made as an examination by the physician for the diagnosis 
of disease. While it is not all of dentistry to discover carious con- 
ditions, and prepare and fill cavities, these constitute the larger part 
of its employment. 

Every one who comes to the dentist for consultation and advice 
is entitled at once to a thorough examination of his teeth. He has 
a right to expect that no carious spot shall remain undiscovered. 
Every continuing patient should have such an examination at regular 
periods, and should be notified of the time if he fails to remember it. 
Examinations at stated periods are of the greatest importance with 
young people. They should be made in all cases at least twice each 
year; as a general rule once in three months; with some children, 
under special conditions, oftener. 

A systematic record should be made not only of conditions requiring 
operations soon, but of those which threaten danger at some future time. 

REGIONAL DIVISIONS FOR EXAMINATION. 

First. — Those pertaining to lines of union (so apt to be imperfect) 
between the enamel plates, on the occlusal surfaces of bicuspids and 
molars, the lingual aspect of upper incisors, and in the buccal or lingual 
grooves of molars. 

Second. — Gingival — regions bordering or beneath the gum tissue, 
particularly those upon the labial and buccal surfaces from the central 
incisors to the last molars. 

Third. — Proximal — those surrounding and including the contact 
points of the teeth, particularly the surfaces immediately rootward from 
those points. 

127 



1 28 EXAMINATION OF TEETH FOR FINDING OF CARIOUS CAVITIES. 

Fourth. — Marginal — along the lines of former operations, at the 
edges of fillings and crowns. 

SYSTEM AND METHOD. 

There should be a regular system of examination and a particu 
lar method of marking diagrams. The writer has adopted the follow- 
ing rules. The lower teeth are examined first, with the patient in a 
position nearly erect, so that when the mouth is opened the light from 
the window falls directly upon the field of observation. 

Examination begins with the central incisor and proceeds to the 
last molar, first on the left, then on the right. Eor the examination 
of the upper arch the position of the patient is higher with the body 
and head inclined backward, so that as before the teeth meet the light 
fairly; and here the order of examination is the same. The diagram 
blank and a pencil should be on the bracket table, and a record made 
of each carious or suspected point immediately upon discovery. 

CONDITIONS FOR EXAMINATION. 

First, Cleanliness. — The first procedure for an examination of 
the teeth is to clean them. Not only must they be freed from calcareous 
deposits but as far as possible from stains. In no other way can every 
surface be brought to view and imperfections noted. The use of the 
scaler will often reveal points of sensitiveness or the hidden margin of 
a cavity. One should never pass an opinion as to the number and 
extent of cavities, or the probable cost of operations, till he has been 
permitted to put the teeth in a proper condition and make a recorded 
examination. 

Dryness. — Cleanliness of surfaces having been assured, the next 
precaution necessary is freedom from moisture. No accurate ex- 
amination can be made of a wet surface. The beginnings of decay 
are seen imperfectly or not at all through films of mucus and saliva. 

For an examination of the upper teeth so far as may be without 
the use of the dam, a cotton roll, or strip of lintine, or a thick piece of 
spunk is laid between the alveolar process and the lip or cheek, while 
the patient is requested to keep the mouth steadily open. 

Freedom from moisture for a corresponding examination of the 
lower teeth is not easily assured. The saliva ejector, valuable in all cases, 
is here quite indispensable. If the operator has no assistant the patient 
himself may render service. A long roll of cotton or muslin is held 
down on each side of the alveolar ridge. For the left side, assuming 
the operator to be right handed, he will hold with the forefinger of his 



CONDITIONS FOR EXAMINATION. 1 29 

left hand the roll between the tongue and the ridge, the assistant (or 
patient) holding the other firmly between the ridge and the lip. On 
the right side, per contra, the assistant will hold the roll against the 
lingual side of the alveolar ridge, the operator that next the cheek. 

After drying the teeth with spunk and warm air they are rubbed 
well with alcohol on cotton and dried again. Where secretions are 
specially viscid and hard to remove it is well to precede the alcohol 
with pumice. After this treatment the teeth present a different 
appearance. Pits and fissures are revealed in the occlusal, lingual 
and buccal surfaces; also shadows and color spots that often indicate 
proximal decay. 

Having obtained dry surfaces, the operator with a good eye, sharp 
exploring instrument and a magnifying mirror, will be able to discover 
carious spots of all classes save one; but that one is perhaps the most 
insidious and dangerous of all — the decay which has its beginning 
close to and directly rootward from the contact point of a tooth. 
These are the decays that sometimes penetrate deeply with an open- 
ing so small as to be hardly discoverable by the finest point of an 
instrument. Unseen and unsuspected, their ravages proceed till a 
large extent of dentin is disorganized, and the enamel of the occlusal 
surface is so undermined that it breaks down suddenly under stress. 
These are the cavities that patients will tell us, "Came all at once," 
because so long as the enamel stood over the chasm there was nothing 
to indicate its presence. 

A common practice is that of depending on the evidence of thread, 
passed between the teeth; but this alone is not conclusive. By the 
roughening or tearing of floss silk it is true that we suspect decay, 
though the rough edge of a filling, or tartar, may produce the same 
effect. But the free passage of floss is not conclusive evidence oj a healthy 
condition. The surface of the tooth may seem perfectly smooth to the 
thread over a spot of unbroken, dead enamel and a sepulcher of dentin. 
In other words the thread will show us plainly very often where decay 
is, but is unreliable for determining where decay is not. 

The only conclusive method is to get separation for vision and 
instrumental exploration. Where the slightest doubt exists as to the 
integrity of teeth at these points, the rubber dam should be used in 
association with the mechanical separator. With the dam in position 
we are certain of dryness, and there is no call for haste in the examina- 
tion. From four to six teeth may be included at once, and their 
proximal surfaces examined in succession. 

By the use of the mechanical separator, sufficient space may be 
9 



130 EXAMINATION OF TEETH FOR FINDING OF CARIOUS CAVITIES. 

obtained nearly always in a few moments for a decisive exploration. 
A bit of space with a gleam of light makes a world of difference in the 
field of observation. Where before no sign of decay was seen, it may 
be that a speck of discoloration, brown or whitish will appear. A 
delicate steel point finds an opening, a sharp, thin chisel breaks the 
enamel roof, and the excavator possibly reveals a deep extension of 
decay. A condition such as this we have no right to overlook. We 
should know positively, either that it does or does not exist. We have 
no right to dismiss an examination with the word or thought, "I 
guess that's all right." It is our business to know. Opinions fathered 
by wishes have no value. 

RECORDS OF EXAMINATION. 

The dentist should keep himself supplied with pads of examination 
blanks such as are kept in stock by the supply houses. Each blank 
should exhibit a diagram of the teeth, both deciduous and permanent, 
with lines for name and date. 

In some cases it is well to make the first record tentative — pre- 
sumably incomplete. Pursuing the methods first described, the teeth 
are surveyed as thoroughly as may be without the employment of dam 
and separator. The diagram is marked for every cavity and fissure 
that is positively indicated, and at every proximal line wmere the least 
uncertainty exists an interrogation point ( ?) is placed. 

After other operations have been concluded, the doubtful spaces 
are examined one by one with the aid of dam and separator. If there 
is found in one place nothing to do, well. If in another but superficial 
decay, it is polished and medicated with reference to the adage, "A 
stitch in time saves nine." If a cavity is discovered, separation is 
increased and a filling, temporary or permanent, introduced. 

When all this is done the operator may truly feel that no interest 
in the case consigned to his care has been neglected. 

CONCLUDING NOTES. 

Special care should be taken to examine along the subgingival 
margins of gold crowns, especially those placed over teeth with living 
pulps, where the right preparation could not have been made and 
there was necessarily an ill fitting band. Also careful exploration should 
be made about the margins of Logan and other bandless crowns for 
caries that may have begun in the root. For a complete, visual 
examination of cavities beneath the gingival gum, a thin bladed retrac- 



CONCLUDING NOTES. 131 

tor is convenient, and often it is necessary to control hemorrhage with 
carbolic or trichloracetic acid or adrenalin chloride. 

Failure to examine for decay beneath fillings of unfavorable ap- 
pearance is a common fault and followed often by serious consequences. 
The dentist is apt to take too much for granted as to conditions beneath 
fillings made of all sorts of mixtures that have gone under the general 
name of amalgam. We should not be prevented by a false conservat- 
ism from thorough examination in these cases. We should make 
doubly sure that our insidious enemy, caries, does not "steal a march" 
on us in the tattered uniform of a friend. 

A small keen hoe or hatchet excavator will oftentimes penetrate 
a dead enamel wall and reveal a cavity better than a delicate pointed 
explorer. 

No service rendered by the dentist should entitle him to better 
compensation on the basis of time than that involved in a careful 
examination of the teeth. 



1 



CHAPTER VIII. 

SEPARATION OF TEETH PREPARATORY TO 
OPERATING ON CAVITIES IN THE PROX- 
IMAL SURFACES. 

BY GARRETT NEWKIRK, M. D. 

Restoration is the watchword of operative dentistry. Simply upon 
the forms of the teeth depend their relations one to another and to 
their surrounding tissues, and together with color, their appeal to the 
esthetic sense. 

Among the many considerations necessary in the restoration of 
tooth forms, and one of the most important, is that of the interproximal 
space. This has a definite relation to the forms and contact points 
of the teeth involved. For the first adequate study and presentation 
of this subject the profession is indebted to Dr. G. V. Black, through a 
paper read by him before the Odontographic Society of Chicago, and 
published in the Dental Review, 1890. Up to this time and for 
many years previous the best operators had often advocated the 
restoration of the natural forms of teeth largely as a matter of idealism, 
but none had grasped the subject in all its relations. Dr. Black set 
forth the importance of a normal interproximal space for the conser- 
vation of healthy gum tissue, to secure the best conditions of cleanliness, 
to prevent the lodgment and impaction of food, to allow the ready 
cleansing of the adjacent surfaces, to insure in large measure the 
permanence of fillings, to promote the comfort of the patient and 
satisfaction of the operator — all this depending of necessity on the 
true proximal contour of the teeth, in accordance with nature's plan. 

Separation for dental operations, by whatever method, has for its 
object the assistance of the operator in the restoration of tooth forms, 
and the preservation therewith of- healthy interproximal gum tissue. 
Without separation preparatory to filling, it is impossible to secure the 
necessary contours. 

Separation may be of two sorts, first, by the slow pressure of some 
expansive material like wood, cotton, linen tape, rubber or gutta- 
percha, continued for hours or days, and denominated "previous;" 
second, by a driven wedge or one of the mechanical appliances, coin- 
cident with the operation of filling and styled the "immediate." 

*33 



134 SEPARATION OF TEETH. 

Both methods are valuable and necessary, each in its place. As a 
rule the previous should be followed by the immediate, for whatever 
space has been obtained beforehand should also be held during the 
several stages of operative procedure. 

PREVIOUS— SLOW WEDGING. 
The writer will say at the outset that the longer he continues 
in practice the less he depends on very slow wedging for the separation 
of teeth. He is more fearful than formerly of inflicting permanent 
injury to the tissues involved — viz., the pericemental membranes, the 
interproximal alveolar wall, and the over-lying gums. All these 
tissues will endure a certain amount of pressure with temporary dis- 
placement, and return to their normal positions unharmed when the 
pressure is removed; but the pressure should not be greater nor longer 
continued than is absolutely necessary to the restoration required. 
It involves primarily the question of blood supply — a diminution here 
and an increase there within the various parts involved. This may be 
illustrated by any one in a moment. Place the ends of your thumbs 
together so that the free margins of the nails overlap. Press these 
one upon the other alternately and repeatedly, and watch the blood 
pressure as it changes beneath each nail, the red and the white coming 
and going, one congested, the other anemic. This is precisely what 
takes place in the tissues surrounding the root of a tooth when pressure 
is brought to bear for separation. Ere long if pressure is not relaxed 
absorption begins. It follows, therefore, that whenever the "im- 
mediate" method of separation can be employed judiciously, it is 
the one to be preferred. 

GUTTA-PERCHA. 

Slight, non-irritating separation may be made to great advantage 
in many cases with gutta-percha, this being used at the same time as a 
temporary stopping. 

As we know, it is often advisable, sometimes unavoidable, that 
such fillings should be inserted for a period of days or weeks. In 
these cases it is possible to make the material accomplish the double 
purpose of protection and separation. By the use of considerable 
force with a broadfaced burnisher as the material slowly hardens in 
the cavity, it may be so compressed as to make it elastic — like rubber, 
only in smaller measure. The effect will be increased if the gutta- 
percha is inserted while the teeth are held slightly apart by the me- 
chanical separator, which should be kept in place till the filling is cold. 
Then, the gutta-percha answers well if it simply holds the space 



COTTON. 135 

obtained by the separator till the next sitting, when by re-application 
of the instrument the space may be increased, probably to the full 
extent necessary. 

Gutta-percha is further useful as a separating material in that 
the gum tissue that sometimes overlaps the gingival margin of a 
cavity may be crowded back from the enamel edge — or from the 
cemental border of an extruded tooth — making possible a clearer 
view of the parts, and better preparation for the rilling. But this 
must be done with extreme care, otherwise serious injury may be 
inflicted by over-pressure. Years ago it was advised by some to leave 
the fillings much over-full, in order that the material might be forced 
down and spread by the cusps of the occluding teeth, allowing it to 
remain for weeks or months. In some instances the effects of this 
practice were disastrous. The interproximal gum tissue was injured 
or destroyed, and articulation of the teeth seriously interfered with. 

Whenever it is purposed to use a temporary stopping for separa- 
tion, all over-hanging walls should be vigorously chiseled away and 
decayed matter removed from the cavity, both for medical treatment 
and to give a firm base for the pressure to be exerted. And, as a 
rule, it pays in satisfaction and efficiency to use the rubber dam. 

In this connection it seems best to quote a paragraph from Dr. 
C. N. Johnson's work on the Principles and Practice of Filling Teeth: 
"To economize time in the management of these cases, it is well for 
the operator, on examining a mouth where several fillings are needed, 
to select these proximal cases at the first sitting and pack gutta-percha 
in each of them. He may then proceed with other work, and by the 
time that is completed some of the teeth thus wedged will be found 
ready to operate upon. The more stubborn cases may be left till 
the last, and, if necessary, the gutta-percha may be renewed in these 
as the other operations are in progress." 

In speaking of this material it should be understood that the 
writer has in mind not merely that known as "sheet" or "base-plate," 
but the various kinds of prepared gutta-percha sold by the dealers 
in convenient form for use. They are easily worked but inferior to 
the old-fashioned sort in resistance to wear, and not so elastic. The 
gray gutta-percha is preferable to the pink only for its appearance 
in conspicuous places. 

COTTON. 

Among the first of materials used for separating teeth was cotton, 
in the form of compressed pellets, pressure depending on the absorp- 



I36 SEPARATION OF TEETH. 

tion of moisture; and it is still used by some almost exclusively. As 
a separator merely it is more effective than gutta-percha, and may be 
preferred whenever a considerable space is demanded within a limited 
time. As a rule it produces no great soreness, and if the teeth are 
held steady by the mechanical separator during the subsequent oper- 
ation, ordinary, careful malleting is well borne by the patient. 

But the cotton pellet is of course unfit for a temporary stopping 
and should not be used for more than a day without change. If 
saturated first with sandarac varnish as it sometimes is, making it 
quite impervious to moisture, it is no better than gutta-percha for 
separating, and by no means so good a filling. 

Cotton is particularly valuable for making space between the 
incisors, or between a cuspid and a lateral incisor. As a rule the pellet 
should be introduced from the lingual direction, and, with a thin- 
bladed instrument pressed toward the incisal borders of the teeth. 
It is readily seen that by crowding the material from the base toward 
the apex of the interproximal triangle we secure the advantage of two 
inclined planes along the teeth. Now, if first a piece of waxed thread 
shall have been introduced rootward, it may be drawn down upon 
the pellet, the ends carried through incisally and tied firmly so as to 
give additional compact to the material. Also the ligature prevents 
crowding out of the cotton toward the tongue or the lip, and the whole 
force of expansion will be directed against the teeth. As a form of 
cotton for this and many other purposes the writer is partial to "lin- 
tine" or "cottonoid," as bought in sheets. 

RUBBER. 

An easy method of separating — easy for the operator— is that of 
stretching and drawing between the teeth a piece of rubber, that may 
be cut from a good sized elastic band, or from strips of different thick- 
nesses and widths supplied by the dealers. But these if kept long 
on hand deteriorate in quality and become worthless. In a small 
proportion of cases, with phlegmatic patients, where teeth have 
short crowns with long roots and are very hard to move, one may be 
justified in using a piece of rubber, narrow and not too thick — to 
get a " start" for the space required. Then, if the mechanical separa- 
tor is insufficient, some other material should be used to induce further 
separation gradually. 

Nearly always, if the elastic quality of rubber is depended on 
entirely for a considerable movement of the teeth, much annoyance 
or real suffering will be experienced by the patient, not only through 



WOOD. 137 

the period of wedging, but during the operations to follow. While 
not easy to account for, it is a fact of experience, that the pressure 
of elastic rubber between the teeth gets "on the nerves" of a great 
many people as nothing else will. One risk of using the rubber is 
that of injury to the gum tissue. As the material contracts labio- 
lingually it bulges into the interproximal space toward the gum, and 
indeed is likely to slip upon the surfaces of the teeth in that direction. 

WOOD. 

The wooden wedge for separating teeth has been much employed. 
Of the many woods recommended at various times all have been 
quite discarded except the orange wood, which is supplied in neat 
bundles by the supply houses. Where one suspects the presence of 
a small proximal cavity in a very close space, in the mouth of a sensitive 
person, where the insertion of cotton or gutta-percha would be difficult 
or ineffective and rubber inadmissible, where allowable force with 
the mechanical separator moves the teeth but slightly and an increase 
of space must be had by the slower process, then, in the slight space 
gained by screw force, we may insert a thin wedge of wood, by hand 
pressure merely or with one or two light taps of the mallet. The 
wedge may then be separated from the stick with cutting pliers made 
for the purpose. If, however, before its insertion a sharp notch is 
cut well around at the base of the wedge, it will afterward break off 
readily from the body of the stick, and, as a rule, with less jar than 
that from the pliers. 

On removal of the separator the wedge is left snug in place, where 
by slow swelling under moisture it separates the teeth. 

TAPE. 

Some practitioners have been partial to waxed linen tape of various 
widths, for slow separation. The unrolled tape is dropped into hot 
beeswax, let cool, and is then stripped of adherent wax. With slow, 
persistent pressure, this thin tape may be crowded between the teeth, 
and usually without the aid of a mechanical separator. Otherwise, 
in place of the screw separator one may use a thin, narrow steel wedge, 
at the end of a strong handle, that the operator may if he chooses 
make for himself. This can be inserted near the necks of the teeth, 
and by hand pressure alone will induce sufficient space between the 
crowns for the insertion of tape or thin wood. The ends of the tape 
may be cut close with a very sharp knife or fine pointed scissors. 
The best scissors that I have found for this purpose, and that I keep 



I30 SEPARATION OF TEETH. 

on the bracket for general use, is a small " manicure" pair with the 
extreme sharp point of each blade ground away. 

Another method of preparing the tape is to dip it in a thin solution 
of gutta-percha in chloroform, and then let the chloroform evaporate. 
This leaves the tape permeated with a film of gutta-percha, which 
makes it very tough and impervious. It will therefore not deteriorate 
in the fluids of the mouth as rapidly as waxed tape. 

It is well to remember that wherever slow wedging is necessary, 
the chief difficulty is overcome when the first slight space has been 
secured for a day. 

THE MECHANICAL SEPARATOR. 

It is axiomatic in the mechanical world that, wherever a certain 
thing is to be done in a particular way, a specific machine accurately 
made, and intelligently directed, will secure results more uniform 
and definite than are possible by the varying, individual hand method. 

Operative dentistry consists largely of a series of mechanical 
problems, and, wherever conditions admit, the principle above stated 
holds good. To a celebrated business man has been accredited the 
statement that he never would do any sort of work himself that he 
could hire done as well or better by some one else. We may say in 
like manner of any mechanical operator that as a rule he cannot 
afford to do by direct effort that which may be better done by an 
intermediate mechanical contrivance. As a recent example of this 
principle we have the anatomical articulator, which eliminates much 
of experiment and guess work in the proper arrangement of artificial 
teeth. 

The separation of teeth as considered within the scope of this 
chapter is a mechanical process, and we wish to know how far it may 
be accomplished by the application of screw and wedge forces, in a 
manner positive and definite. What are the requirements of such an 
appliance, and have they been successfully met? 

First : The points of pressure must be aside and far away from 
the median line of the proximal surface; otherwise they will intrude 
upon the field of operation, or, if carried too far rootward will press 
dangerously on the interproximal gum tissue. 

Second: The pressure having to be well aside from the median 
line, it should be upon both sides equally. 

Third: As the separating applies to both teeth, there should be 
necessarily four distinct points of pressure at regular distances. 

Fourth: The points must be far enough over the crown so that 



. 



THE MECHANICAL SEPARATOR. 



J 39 









Fig. 106. — Perry Separators. 



140 SEPARATION OF TEETH. 

their tendency under pressure will be to move rootward, otherwise 
they would be likely to slip off; but they must at the same time be 
stayed, to prevent their going too far, with impingement on, and danger 
of injury to, the soft tissues. 

Fifth: The four points make necessary two bars, each with a 
right and left hand screw, through which forces may be exerted alike 
in both directions. 

Sixth: While the principle of the instrument is everywhere the 
same, proportions of the parts must vary for purposes of adaptation 
to the different forms and classes of teeth, considered in relation with 
their interproximal spaces. This fact precludes the construction 
of any so-called "universal" separator which shall be equal to the 
different forms, each in its special field. Either the "universal" 
will fail to meet all these requirements — for example, having points 
on one side only with an opposing wedge; or, it will be intricate and 
cumbersome, lacking the simplicity of the special instrument. 

Just as possible a universal saw for the carpenter, or a universal 
pattern for a coat, as of one separator adapted to all parts of the 
mouth. It is altogether probable the one who owns a "set" of sepa- 
rators will employ one form or another much oftener, and with greater 
satisfaction in every case, than the possessor of a "universal" only. 
"The best is none too good," as relates to the instruments of operative 
dentistry. When one is selecting an appliance that ought to last 
throughout his professional life, he can ill afford to ignore this truth. 
It is here that the mistake of a moment is oft the detriment of years. 

THE BEST. 

The author has no hesitation in saying that the principles of 
mechanical separation have found their best expression in the "set" 
invented by Dr. S. G. Perry, originally four in number, now six. 
These various forms are marvels of ingenuity, adaptation and sim- 
plicity. Artistic of construction yet strong, there is slight chance of 
their being superceded. 

The usual objection offered to the Perry set is that it is expensive; 
but, if we take into consideration both usefulness and durability, in 
the long run it will prove the best investment. Few dentists would 
think of going into practice without a good chair or first class engine; 
and yet, one might perform good operations over a plain arm chair 
with a head-rest. The writer is positive that he would rather use a 
cheap chair till he could make enough money to buy a good one, than 
to practice one month without the Perry separators. 



THE BEST. 141 

Let us enumerate, briefly, some of the advantages and uses of 
mechanical separation. 

First: In Examination of Teeth for Carious Cavities. 

The important office performed by the separator in this connection 
has been considered in chapter VII. 

Second: Preparatory to Slower Wedging and Temporary 
Stoppings. 

Where it is evident that sufficient space cannot be had with the 
mechanical separator alone, it may be used to obtain room for the 
insertion of cotton, wood or gutta-percha; and in like manner for the 
introduction of gutta-percha as a provisional stopping. 

Third : In the Preparation of Cavities for Filling. 

Time and observation demonstrate to every experienced operator 
that faulty preparation is probably the commonest fault of dentistry. 
Back of this fault very often lies the fact of insufficient space — teeth 
that have had no separation; or having been separated have nothing 
to keep them apart for operations following: — For what sufficeth it 
to wedge with cotton or wood, and make no provision for holding the 
space obtained? 

The mechanical separator will do this; and it will hold the teeth 
steady, so that the instrument employed, chisel, excavator or bur, 
can be used more accurately, and with less pain or shock to the patient. 
And the separator with four points generally is not in the way of 
observation, does not obtrude in the interproximal space, and holds 
the dam aside for the admission of light. 

It is well to remember, however, that occasionally where w T ide 
lateral extension of a cavity is demanded, either for "prevention" 
or on account of existing decay, a point of the separator may 
impinge upon the field of operation. In such a case the instru- 
ment may be used for preparation of the main cavity and then 
removed. Before removal, however, if sufficient space exists for 
the insertion of a narrow wooden wedge, this may be employed to 
hold the space, both for the final preparation and the beginning of 
the filling. 

Fourth: For the Insertion of Gold Fillings. 

As in cavity preparation, the separator holds the teeth steadily 
in position for instrumental service in filling. It makes the use of the 
plugger more accurate and positive, and the application of mallet 
force less trying to the patient. 

As a rule where a tooth is filled after "immediate" separation 
by one of the Perry instruments, with or without slight wedging before- 



142 . SEPARATION OF TEETH. 

hand, the patient will not complain of any malleting necessary for the 
proper condensation of gold. 

Fifth: In Connection with Porcelain Inlays. 

The mechanical separator may assist greatly in securing access 
for cavity cutting and grinding, facilitates the removal of a matrix, 
or the insertion of an inlay, holds the teeth apart for the final finish 
of the work, especially in connection with the anterior teeth and 
cavities of moderate extension. It may also be used to gain space 
for the removal of inlays that have become loosened, and their re- 
insertion. 

Sixth : Preparatory to Filling with Amalgam or Cement. 

The separator gives the advantages before described for preparation 
and initial space. The teeth are held apart and steady up to the' 
moment of applying the matrix, or with the use of a hand matrix the 
separator may remain in position. 

Seventh : For the Finishing of all Proximal Fillings. 

To give access for fine cutting instruments, finishing files, tape or 
disks, for proper " knuckling," there is nothing to compare with the 
Perry separators. 

In Miscellaneous Conditions Requiring Separation. 

Cases are presented where the interproximal space has been left 
unprotected, where the patient is distressed by food impaction with 
every attempt at mastication and the gums perhaps are continually 
congested and sore, in consequence of previous faulty operations. 
Such teeth are seldom firm in their sockets, and in many cases may be 
separated by the "immediate" method sufficiently for contour restora- 
tions. Not infrequently we find some foreign substance, a piece of 
wooden tooth-pick or berry seed perhaps, imbedded between the 
necks of teeth and hard to dislodge, or, as occurred recently in the 
writer's practice, one may discover a sequestrum of bone as the result 
of arsenical poisoning. In such cases the Perry instrument with its 
widely separable points will render valuable aid. 

Final Considerations. — To adjust the mechanical separator 
easily and deftly requires practice, and the operator must not expect 
smooth sailing in every case at first. With the bicuspid and molar 
forms, the lip of the patient is likely to be lifted up uncomfortably. 
To relieve this at once a smooth steel instrument like the handle of an 
explorer should be inserted at the angle of the mouth and passed 
gently forward, lifting the lip over. 

Whenever the separating points are going higher than they should, 
so as to crowd upon the gums, the screws should be relaxed and the 



. 



THE BEST. 143 

instrument held in proper position while gutta-percha is warmed and 
crowded under the bows. When this is hard (and cooling may be 
hastened with the chip-blower), the rootward movement of the points 
is prevented and separation may proceed. The screws should be 
kept well oiled, both for ease of working and to prevent their wearing 
out. They should be turned on beforehand till the points are at the 
distance apart that will just allow them to slip over the teeth. Then 
with but a little turning the instrument finds its true position, and 
the wrench has less to do within the mouth. 

It is said that some are deterred from using the molar separator 
by what they consider the extreme difficulty of its application in con- 
nection with the rubber dam, for in most cases the clamp must be 
dispensed with. It is not hard to obviate this difficulty. Apply 
the dam as usual and the clamp temporarily. Then ligate, if nec- 
essary drawing knots of thread from both sides into the furthest inter- 
proximal space. After exchanging the clamp for the separator the 
rubber will rarely become displaced. 

The writer has discovered that in certain unusual cases some 
forms of the separators may be used in a manner not shown by the 
"Directions." For example, one may find molars so small that the 
bicuspid form would apply — or a first molar so much larger than the 
second, or a second so much larger than the third, that the bicuspid- 
molar separator reversed — i. e., with the larger bow forward, will 
best meet the requirement. 

Force should be applied always with immediate reference to the 
feeling of the patient — at first barely to the point where he admits 
that the pressure is uncomfortable — if really painful the screw should 
be turned back a little. One may say to the patient truthfully that 
in a few moments the feeling of undue pressure will pass off. After- 
ward as a rule there will be no objection on his part to quarter or 
half turns of the screws with intervals of rest between. Tact and 
caution on the part of the operator must never relax. The temptation 
to hurry and crowd must be resisted. 

Here, as in relation with other operative procedures, patients 
have their idiosyncrasies. One will disclaim any sense of discom- 
fort whatever, one will anticipate trouble that does not come, while 
another is truly hyper-sensitive and deserving of the most delicate 
consideration. Now and then, once a year possibly, a patient will 
present with whom the separator is impracticable by reason of unusual 
tenderness of the peridental tissues or general nervous timidity. 

Much depends on the attitude of the operator in the first intro- 



144 SEPARATION OF TEETH. 

duction of any appliance that might excite the fears of his patient. 
If we show to the patient, older or younger, the necessity of space 
and the advantages of separation; if we assure him that we shall be 
careful not to carry the pressure beyond the point of reasonable en- 
durance on his part; if we are painstaking further to consult with him 
or her as to the degree of force that may be easily borne, Ave shall have 
little trouble in the use of this most valuable assistant. 



CHAPTER IX. 

EXCLUSION OF MOISTURE FROM THE TEETH 
DURING OPERATIONS. 

BY GEORGE EDWIN HUNT, M. D., D. D. S. 
GENERAL CONSIDERATIONS. 

The desirability of excluding the saliva from tooth cavities about to 
be the scene of operative procedures is based on four considerations. 
First, perfect dryness is essential to secure cohesion of gold. Second, 
the saliva is laden with micro-organisms, many of which in their life 
processes form by-products detrimental to tooth structure, and, there- 
fore, exclusion of the saliva is necessary that the tooth structure may be 
sterilized. Third, saliva obscures and distorts the view of the walls 
and angles and dryness is desirable that a perfect view of the cavity 
may be obtained. Fourth, the dentin of teeth with living pulps is much 
more sensitive when wet and dryness is necessary to diminish the pain 
of excavating. 

Before Dr. Sanford C. Barnum, of New York City, invented the 
rubber dam and gave it to the profession in 1864, dryness of tooth 
structure was obtained by the use of napkins, cotton and other absor- 
bents. The exclusion of saliva by such means was necessarily of com- 
paratively short duration and extensive operations with cohesive gold 
were impossible, although the more skillful practitioners in those days 
acquired a degree of dexterity in handling napkins and absorbents that 
is seldom seen among our contemporaries. Since 1864 nothing has 
been found to equal rubber dam for excluding the saliva during lengthy 
or intricate operations, although absorbents may be used in many 
short operations with perfect success if they are used intelligently. 
It is therefore necessary that the operator become skilled in the ad- 
justment of the rubber dam, to the end that it may be used to the best 
advantage and with a minimum amount of annoyance and discomfort 
to the patient, to whom, under the most favorable circumstances, it is 
a trial. Many operators do not use the rubber dam as often as they 
should. This is usually due to the fact that the operator is unskill- 
ful in adjusting it and dreads the time and trouble his unskillfulness 
requires to place it in position. In this, as in all other manual opera- 
tions, practice alone will bring ease of manipulation. 
10 145 



140 EXCLUSION OF MOISTURE FROM TEETH DURING OPERATIONS. 

THE USE OF RUBBER DAM. 

Rubber dam is classified as heavy, medium and light in weight, 
according to its thickness. Heavy and light dams each have their 
advantages and disadvantages. Heavy dams are less likely to be torn 
in adjustment, they will more often remain in place without the use 
of ligatures or clamps, and they are not easily caught up by revolving 
burs, stones, discs or other engine instruments. Light-weight dams are 
more apt to be torn in adjusting, usually require ligatures or clamps 
to hold them in place, and are readily caught up by engine instruments 
by which they may be torn or cut. However, owing to the conforma- 
tion of the teeth, or their relation to each other, it is often difficult to 
adjust a heavy dam where a light one can be carried to place with com- 
parative ease. Therefore, if but one weight of dam is to be used, a 
medium weight, which diminishes the disadvantages of the two ex- 
tremes, is best. A light colored dam is preferable as absorbing less and 
reflecting more, light. Rubber dam, like all rubber, deteriorates with 
age and is sometimes ruined by the manufacturer in vulcanizing. A 
simple test for quality is to stretch it well with a thumb or finger and 
note whether it returns to its original shape without bagging or tearing. 

Size and Shape. — For operations on the anterior six teeth a trian- 
gular shaped piece of dam will be found both efficient and economical. 
This may be obtained by cutting diagonally a piece from six to nine 
inches square, the long side to be against the upper lip when adjusted. 
For the posterior teeth a piece from seven to nine inches square will 
be found most useful. It is poor economy to use smaller pieces as the 
edges will be found to be in the way and imperfect exclusion of saliva 
from the exposed surface of the dam may result. 

The Holes. — Holes permitting the passage of the tooth crowns 
may be made in different ways. Various sized single punches may be 
obtained from hardware or dental supply dealers or a triangular 
punch, capable of making three different sizes of holes, may be used. 
With these, the dam is placed on a block of wood and a hammer or 
mallet used on the punch. Very few operators now employ this 
method, however. The most efficient method is by the use of one of 
the improved rubber dam punches on the market, having a revolving 
steel disk with four or more round holes, varying from f of a milli- 
meter to 3 millimeters in diameter, which engage a pivoted cone- 
shaped steel plunger, punching the desired sized hole in the dam. 

If a punch is not available, the rubber may be tightly stretched over 
the tapering round handle of a gold plugger, when the application of 
a sharp knife blade to the tense rubber on the side of the handle will 



THE USE OF RUBBER DAM. 



147 



result in a clean cut, round hole. The size of the hole may be varied 
by nicking the rubber at a greater or less distance from the plugger 
end and a little experience will 
enable the operator to thus 
cut holes of any desired size. 
As a rule operators are more 
apt to use holes too small 
rather than too large. 

The distance between the 
holes will vary in different 
cases, from 2 to 4 millimeters 
being the usual distance in 
medium weight rubber. The 
lighter the rubber the further 
apart the holes should be. 
In abnormal cases, where the 
teeth are separated or the gum 
tissue has receded, the holes 
may have to be much further 
apart. In normal cases, teeth 
with long crowns and pre- 
senting large interproximal 
spaces, require that the strait 
of rubber between the holes be 
wider than in cases where the 
crowns are short and the inter- 
proximal space small. These 
matters should be noted, for 
if the distance between the 
holes is greater than necessary, 
the rubber will bag in the inter- 
proximal space and be in the 
way, and if it is less than it 
should be the strait of rubber 
will slide down between the 
interproximal gum tissue and 
the proximal surface of one of 
the two teeth, exposing the 

„„_ .' i«ii Fig. 107. — Rubber Dam Punch. 

gum tissue and causing a leak. 

This latter will also occur if the holes punched are too small, requiring 

excessive stretching of the rubber to encircle the neck of the tooth. 




I48 EXCLUSION OF MOISTURE FROM TEETH DURING OPERATIONS. 

The location of the holes will be governed by the location of the 
tooth to be operated upon. In all cases the holes must be far enough 
from the upper edge of the dam to permit the rubber to cover the upper 
lip after adjustment. If the patient has a moustache, the holes must 
be far enough from the upper edge of the rubber for the latter to cover 
the moustache. But in no case should the rubber cover the nostrils 
or interfere with breathing through them. For teeth on the right or 
left of the median line a corresponding variation to the right or left of 
the median line of the dam is desirable and, in a general way, the curve 
of the holes should correspond to the curve of the dental arch. The 
novice should hold the rubber dam against the teeth to be isolated and 
note the approximate location of the holes necessary to have the dam 
cover both lips properly after adjustment. 

The number oj teeth isolated by the dam is a matter of importance. 
In those abnormal cases where the rubber is adjusted with great 
difficulty, owing to the shape of the teeth, wear on the occlusal sur- 
faces, unusual resistive power of the facial muscles or other cause, and 
in treatment cases where the operation is short and easy of execution, 
the number of teeth isolated may be much reduced, sometimes even 
limited to the one tooth to be operated upon, but in nearly all cases 
several teeth should be included. This is desirable in that it gives 
better light and better access by getting the rubber out of the way 
and diminishes the danger of catching up the rubber in revolving engine 
instruments. The opportunity for error in operative procedures is 
sufficiently large without adding to it inconveniences within the control 
of the operator, yet many operators make the mistake of including too 
few teeth when adjusting the dam. In all distal surface operations 
the tooth lying distally should be included. In operations on the 
anterior teeth, for convenience sake, from four to six teeth should be 
isolated. In operations on the molars and bicuspids the teeth anterior 
should also be isolated up to and including either the lateral or central 
incisor. On account of its anatomy the cuspid is an unsafe tooth at 
which to stop. It has less of a constriction at the neck than any of the 
other teeth and the dam, whether ligated or not, is more likely to be 
worked crownwards by the action of the tongue and lips than with 
other teeth. For this reason, in operations on the lateral incisors the 
rubber should include the first bicuspid on that side and in operations 
on the bicuspids and molars should extend forward to one of the incisors. 

Adjusting the Dam. — Prior to adjusting the dam, if the cavity 
reaches the occlusal surface or incisal edge, the operator should care- 
fully note the articulation and the landmarks of mastication as a guide 



THE USE OF RUBBER DAM. 1 49 

for the fullness of his filling. If the teeth set very closely together and 
especially if the occlusal surfaces and incisal edges are badly worn, 
as in an "end to end" bite with the "ball and socket" tempero- mandib- 
ular articulation, a waxed thread should be passed between the teeth 
about to be isolated and all calculus and rough or sharp edges of 
fillings or cavities revealed by the fraying of the thread, removed and 
smoothed so the dam will not be torn. Dr. C. N. Johnson suggests 
that a thin broad instrument like a gum depressor or thin spatula, 
forced between the teeth and carried rootwards by a see-sawing motion, 
will smooth rough or jagged edges of enamel left by caries and permit 
the safe passage of the dam. A rubber or wooden wedge will also 
move the teeth in a few moments sufficiently to permit the passage of 
the rubber at any particularly difficult point. Just before proceeding 
to adjust the rubber the tooth crowns should be swabbed with a pledget 
of cotton dipped in absolute alcohol, to remove inspissated mucus, 
food debris or other infectious matter which might be crowded under 
the free margin of the gum in adjusting the dam. 

On the anterior teeth and also on the posterior teeth when it is not 
intended that a clamp be used, the dam should be adjusted first over 
the tooth nearest the operator, taking the others in succession. By 
this method the best view of the field of work is obtained. The dam 
should be stretched labially or buccally and lingually by the thumb 
and fingers of the right and left hands and worked rootwards by a see- 
saw motion until the rubber is well down to the cervix and the strait 
between the holes is pressing down on the interproximal gum tissue. 
In performing this operation on the anterior lower teeth the operator 
stands at the right and slightly in front of the patient, the fingers of 
his right hand guiding the rubber on the labial aspect of the teeth, his 
left hand fingers within the oral cavity guiding the rubber on the lingual 
aspect. In adjusting the dam on the anterior upper teeth the position 
of the hands is reversed, the fingers of the left hand caring for the labial 
and those of the right piloting the lingual portions of the rubber. The 
position of the hands will be naturally suggested by the convenience 
of the operator in adjusting the dam on the posterior teeth, the right 
hand guiding the buccal and the left the lingual portions of the dam 
while operating on the left side of the mouth and the positions being 
reversed on the right side of the mouth. As a rule simply hanging 
the rubber on the teeth as described is all that is necessary at this time 
to keep it in position but if there is a decided tendency for it to slip off 
or to be thrown off by the action of the tongue and lips, a piece of waxed 
floss silk thread should be passed down the distal surfaces of the end 



I50 EXCLUSION OF MOISTURE FROM TEETH DURING OPERATIONS. 

teeth beyond the point of contact. This will hold the rubber in place 
temporarily. 

In difficult cases, where the teeth are closely in contact and have 
broad contact surfaces, or perhaps facets worn on the proximal sur- 
faces, a little vaseline on the rubber between the holes will facilitate 
its passage between the teeth. Sometimes the use of a waxed silk 
thread by an assistant or by the operator is necessary to carry the strait 
of rubber rootward past the point of contact. In some cases the pas- 
sage of the rubber can be accomplished by stretching it well and tilting 
it so the edge of the rubber strait presents at the point of contact in- 
stead of the width. If the rubber is securely hung over the first tooth 
or teeth and an especially difficult point is reached, it may be passed, 
care being used not to confuse the holes and tooth crowns, and the rubber 
adjusted over the remainder of the teeth, the operator finally returning 
to the refractory one. Occasionally difficulty will be experienced 
on account of involuntary movements of the cheek, lip and tongue mus- 
cles. Dr. C. N. Johnson recommends that the patient be given a hand 
mirror with which to view the operator's efforts. The patient's at- 
tention thus being directed to the difficulty, the muscles will usually 
be voluntarily relaxed. In obstinate cases, if this method does not 
succeed, the application of the dam should be limited to as few teeth 
as possible. 

Having hung the rubber on the teeth temporarily the lower edge of 
the dam should be raised and a napkin placed in position over the lower 
lip so the dam will not come in contact with the lip or with the chin or 
cheeks, and napkin and dam secured by the rubber dam holder. A 
saliva-wet dam is a great source of discomfort and annoyance to the 
patient if in contact with the skin. The patient being fairly comfort- 
able and the lateral edges of the dam held back out of the way, the 
operator is free to return to the adjustment of the rubber to the teeth. 

To insure a saliva-tight joint the edge of the rubber must be turned 
rootward so it will pass between the tooth and the free margin of the 
gum. This can often be accomplished by simply stretching the dam 
labially and lingually and working it well rootwards bef6re releasing it. 
Sometimes a flat instrument, like a spatula, run around the cervix, 
will turn the dam margin rootwards. Ligating the tooth will always 
accomplish this result. 

Ligating the Teeth. — Ligatures and clamps should only be used 
when they are necessary to the success of the operation, but they are 
often necessary. If the carious cavity is a proximal one, the tooth 
should be ligated to insure security of the dam. For the same reason it 



THE USE OF RUBBER DAM. 151 

is well to ligate the tooth facing the cavity. Often the end teeth of those 
isolated will need ligating in order that the action of the tongue, cheeks, 
and lips may not force the rubber crown-wise. On molars and bicus- 
pids, the clamp, as will be explained later, takes the place of a ligature 
on the tooth to which it is applied. In operations on incisal edges or 
occlusal surfaces, or in treatment cases it is often unnecessary to use 
ligatures at all. 

The ligature should be a well waxed floss silk thread made for the pur- 
pose. If the interproximal space is large enough to permit of it, the liga- 
ture may be passed from labial or buccal to lingual between the point of 
contact and the interproximal gum tissue and returned in the same 
manner. Usually it is better to force it down between the approxi- 
mating surfaces past the point of contact. Having passed it rootward 
down the mesial and distal surfaces of the tooth to be ligated, the ends 
should be gathered up and the portion embracing the proximal and 
lingual surfaces of the tooth carried rootw T ard by traction, the rubber 
preceding the ligature. This will curl the rubber edge rootw r ards, as 




Fig. 108. — Surgeon's Knot. 

desired. Often this is all that is necessary for the retention of the 
rubber and the floss silk may be removed, or, in cases where the inter- 
proximal space is small and the point of contact well rootwards, the 
ends of the thread may be cut off close to the labial surface of the tooth 
and will retain the rubber in position by its wedging action. If com- 
plete ligation is desirable, the first part of a surgeon's knot (see Figure 
108) should be tied and, just before it is drawn taut, traction again 
made rootward, supplementing this, if necessary, by carrying the thread 
rootward w T ith a suitably shaped blunt instrument, as a plugger, used 
on the lingual surface. Having carried rubber and thread fully to 
the cervical constriction, the knot should be tightened and the tie com- 
pleted. The free thread ends may now be cut off close to the knot 
with curved bladed scissors or, if an end tooth, a dam weight may be 
fastened to the ends of the thread and the weight passed back and left 
suspended over the patient's shoulder. This latter method assists in 



152 EXCLUSION OF MOISTURE FROM TEETH DURING OPERATIONS. 

keeping the rubber out of the way of the operator. The remaining 
teeth should now be ligated in rotation, as above described. 

Dr. E. K. Wedelstaedt suggests an effective method of ligating. The 
first portion of the surgeon's knot is made on the lingual surface instead 
of the labial or buccal, and the thread ends again passed through the 
interproximal spaces to the labial or buccal. Strong traction is now 
made on the thread ends and the half completed knot on the lingual 
carried rootwards to the cervical constriction, with a suitably shaped 
blunt instrument. A full surgeon's knot is now tied on the labial or 
buccal surface, completing a double wrapped ligature. 

Sometimes the action of the muscles or the shape of the crown causes 
the rubber to slip crown-wise over the ligature. This is most apt to 
occur with light-weight dams and in the molar region. To obviate it, 
from two to four glass beads may be strung on the ligature and ar- 
ranged at effective points about the cervix of the tooth. Their bulk 
will prevent the rubber slipping over them. Dr. Fernandez suggests 
the use of short pieces of very small rubber tubing as being preferable 
to the beads. Dr. Wedelstaedt suggests tying a small roll of cotton 
in the ligature, to secure bulk. Usually a bulky knot, which may be 
tied in the thread before adjustment, on the lingual and the retaining 
knot on the buccal, will be sufficient. 

To be effective, ligatures must encircle the tooth at the cervical 
constriction. Carrying them to position is painful in some cases and 
painless in others, owing to the extent the gingival gum tissue must be 
forced rootward to allow the adjustment of the thread. As a rule the 
pain felt quickly passes away as the tissue recedes before the pressure 
of the dam and thread, but if it is severe and the ligature absolutely 
necessary, the rubber should be everted sufficiently to paint the gum- 
margin with a two per cent solution of cocaine hydrochlorate. The 
ligature may then be painlessly adjusted and by the time the effect 
of the anesthetic has worn off, the gum tissue will have retracted suffi- 
ciently that pressure is relieved and further pain averted. No per- 
manent injury to the gingival margin need be feared unless the force 
used in adjusting the ligature is brutal enough to tear and lacerate the 
tissues, and with ordinary care the margin will return to its original 
position a few minutes after the removal of the rubber. 

In some cases, where there has been considerable recession of gum 
tissue and, perhaps, of alveolar process, and correspondingly large 
interproximal spaces present, instead of using ligatures, wads of ab- 
sorbent cotton may be packed between the teeth, holding the rubber 
to place. Whatever method is employed, the operator should be care- 



THE USE OF RUBBER DAM. 



SO 



ful to remove all retaining material or appliances before attempting 
to remove the dam. 

Clamps. — Clamps are used to hold the rubber on the tooth and to 
keep it out of the way of the operator. If properly selected and adjusted 
they are harmless and not particularly uncomfortable but if not so 
selected and adjusted they may be detrimental to tooth-structure and 
soft tissues, and very painful to the patient. If the clamp is too small, 
the beaks may bite into the enamel; if it is too large or does not fit the 
tooth, it may be forced rootward and impinge seriously on the soft 
tissues; if carelessly adjusted the gingival tissue may be severely pinched 
by the beaks. The beginner should try each clamp on the tooth 
and note that it encircles the cervix properly, before attempting the 
adjustment of the rubber. A clamp which fits the cervix, even when 
carefully adjusted, may crowd the gum tissue rootwards to some extent 
but, as with ligatures, no permanent injury will result and the tissue 
will resume its original position on removal of the pressure. Cocain 
may be used to deaden the pain of adjustment, if necessary. 

Two forms of teeth are especially difficult to clamp successfully, 
those excessively bell-crowned, on which the clamp tends to slide root- 
ward and impinge seriously on the gum tissue, and those short crowned 
teeth seemingly or really larger at the cervix than at any point crown- 
ward, from which the clamp tends to slip off occlusally. In both cases, 
a perfect fitting clamp will go far to remove the difficulty. Clamps 
have been devised for the bell- crowned teeth, with bows so arranged 
as to rest on the occlusal surface and prevent the slipping of the beaks 
rootward; and it has also been recommended that gutta-percha or 
other plastic material be placed between the clamp-bow and the occlu- 
sal surface, but none of these methods are efficient and a better plan 
is to dispense with the clamp and use a ligature. In many of the short 
crowned teeth it will be found that a cervical constriction exists if the 
beaks only reach it but that the gum tissue overlaps the cervix unduly. 
If this is not the case and the tooth-crown actually narrows occlusally, 
reliance must be placed on a perfect fitting clamp and caution during 
the operation that the clamp be not dislodged. In selecting the clamp 
for these cases preference should be given one with beaks having a 
decided rootward inclination, as is the case with the Ivory number 
14. With such a form the beaks pass between the crown and the over- 
lapping gum tissue until they reach the cervix, with a minimum 
amount of impingement on the soft parts. 

There are many sets of clamps on the market, all with some merit 
and each with their advocates. Ordinarily the operator will use one 



154 EXCLUSION OF MOISTURE FROM TEETH DURING OPERATIONS. 



of a few standard clamps but a large assortment of special forms 
should be available to fit the extraordinary cases which occasionally 
present. 

Usually the only tooth on which a clamp is placed is the posterior 
one of those isolated and in adjusting the rubber on molars and bi- 
cuspids, when a clamp is to be used, the operator should begin with 
the tooth furthest back and work forward. Having selected the clamp 
best adapted to the tooth, the rubber should be adjusted on that tooth 
and the clamp placed in position by means of the clamp forceps. The 
difficulty experienced in practicing this method is that in proportion as 
the clamp is needed for the retention of the rubber, it is difficult to 

keep the rubber on the tooth long 
enough to adjust the clamp. To ob- 
viate this some operators stretch the 
rubber over the bow of the clamp, ad- 
just the forceps to the bow, gather up 
the rubber with the left hand and 
place the clamp in position on the 
tooth. The rubber is then stretched 
with the fingers until it slips under the 
beaks of the clamp and encircles the 
neck of the tooth. The objections to 
this method are that the rubber ob- 
scures the view of the tooth except in 
a few favorable instances where it 
may be held out of the way with the 
left hand sufficiently to permit of the 
crown being seen, and that stretching 
the rubber over the beaks often forces the latter down unduly on the 
soft tissues. The Ivory clamp w r as devised to meet these objections. 
This clamp has buccal and lingual flanges on the beaks, so arranged 
that the bow of the clamp may be passed through the hole in the rub- 
ber and the latter hung on the two flanges. The clamp with the rub- 
ber in position is now taken up by forceps designed for this purpose 
and adjusted on the tooth, the rubber being so stretched over the 
flanges as to bring the tooth-crown into view as the clamp is carried 
to place. The rubber is then slipped rootward from the flanges and 
encircles the cervix. Mesial projections on the beaks keep the rubber 
from obscuring the view of the mesio-cervical portion of mesial cav- 
ities. 

Cervical Clamps. — Buccal, labial and lingual cavities, with all 




Fig. 109. — Ivory Clamps. 



THE USE OF RUBBER DAM. 



155 



or a portion of the cavity lying rootwards from the cervical line, re- 
quire the use of cervical clamps if any clamp at all is used. The 
wide range of location met 
with in these cavities renders 
it desirable that the operator 
have several forms of clamps 
to meet the differing condi- 
tions, although the mechanical 
improvement in some forms 
has been so great in recent 
years that they may be used 
successfully in widely varying 
cases by change of adjustment. 
The Ivory, Keefe and Dunn 
are all useful and have a con- 
siderable range of adjustment. 
The use of cervical clamps 
is often attended by much 
pain, due to forcing the soft 
tissues rootward sufficient to 
allow the beak a bearing on 
normal cementum. If possi- 
ble, the gum tissue should be 
retracted previous to the oper- 
ation by packing the cavity 
with gutta-percha. If the 
cavity is not of a retentive 
form the gutta-percha may be 
held in position with a wire or 
thread ligature. In superficial 
caries where this is impossible, 
the soft tissues may be divided 
by a longitudinal cut and the 
flaps pressed out of the way. 
On completion of the opera- 
tion the incised tissue should 
be pressed into apposition 
and gently massaged with the 

finger tip FlG " IIO -~ Brewer Clam P Forceps. 

Rather than adjust a cervical clamp many operators hold the dam 
to place with a pointed instrument while filling the subgingival por- 




156 EXCLUSION OF MOISTURE FROM TEETH DURING OPERATIONS. 




tion of the cavity and still others prefer to use absorbents in a manner 
to be described later, using amalgam for the subgingival portion in 
molars and bicuspids, and pellets or cylinders of non- cohesive foil in 
the anterior teeth, afterward adjusting the rubber dam and finishing 
the operation with the filling material indicated for the case in hand. 
In all cases where clamps and ligatures are used, as in all other 
steps in operations in the oral cavity, the comfort of 
the patient should be considered, and while the 
operator would grossly err in allowing his regard 
for the feelings of his patient to interfere with the 
perfect performance of the operation, it is often 
possible to save the patient annoyance and discom- 
fort by the exercise of judgment and care. 

THE SALIVA EJECTOR, BIBS, ETC. 

In some cases the required posture of the patient 
or the location of the adjusted rubber dam interferes 
seriously with the swallowing of the saliva. Opera- 
tions on the upper molars, where the chin of the patient 
is elevated and the neck muscles tense, are examples of the first class, 
and the adjustment of the rubber on the lower molars illustrates the 
second class. In some cases, also, the mental state of the patient or 
the pain of excavation will result in an abnormal amount of saliva 
being delivered to the oral cavity. Whether due to larger amounts of 
saliva or to the inability of the patient to dispose of it by swallowing, 
the excess will drool from the mouth and should be 
cared for. Rubber bibs for the protection of the 
patient's clothing may be used or towels placed over 
the chest. The saliva ejector is of great help in these 
cases, by siphoning off the saliva. Occasionally a 
nervous patient will be found who objects to its use 
but many others will stand the pain of excavating 
and the strain of a long operation far better if they 
are instructed in the use of the ejector and allowed 
to manipulate it. The diversion of attention from 
the operation to the manipulation of the ejector is, 
of course, responsible for this. 



Fig. hi. — Ivory 
Cervical Clamp. 




Clamp. 



RUBBER CUPS, COTTON ROLLS AND NAPKINS. 

As has been previously remarked, before the days of rubber dam, 
napkins and other absorbents were the only available means for the 



RUBBER CUPS, COTTON ROLLS AND NAPKINS. 1 57 

exclusion of saliva. In later years some efforts have been made to 
increase the efficiency of the methods employed in using absorbents 
but, in the opinion of the writer, they have been futile. By the old 
methods, absorbents skillfully manipulated will exclude saliva in nor- 
mal mouths for from twenty to thirty minutes, or longer, without 
distressing the patient. For short operations, such as redressing a 
pulp canal or inserting a temporary filling, this is more than ample 
time. The writer has seen large occlusal cavities in lower molars 
filled with non-cohesive cylinders and finished with cohesive foil while 
the saliva was excluded by the use of napkins. The subject of the 
exclusion of saliva by the use of other materials than the rubber dam 
may be divided as follows: — First, the use of rubber cups; second, the 
absorption of the saliva after it flows into the mouth; third, the 
prevention, partially or totally, of the delivery of saliva to the oral 
cavity. 

Rubber Cups. — Rubber cups known as Denham's coffer dam 
shields, fashioned like the cups used for carrying pumice for polishing 
teeth, are used with some success for short operations. The base of 
the cup is of thin rubber. A hole is made in the base with the rubber 
dam punch and the cup adjusted on an Ivory or similar clamp. The 
clamp is then carried to place on the tooth and the rubber slipped over 
the flanges of the clamp as described in the use of rubber dam. In 
pulp canal treatment of lower teeth where the adjustment of the dam 
is particularly difficult, these cups may be used to advantage. The 
saliva ejector may also be used to assist in reducing the amount of 
saliva in the mouth. 

The Use of Absorbents. — Absorbing the saliva after it flows 
into the mouth may be accomplished by napkins or by specially pre- 
pared rolls of absorbent cotton. The manner in which this is done 
will readily suggest itself to the operator. The roll or napkin is ad- 
justed in a V shape with the free ends to the anterior, the bottom of 
the V just posterior to the tooth to be operated on and the roll resting 
against the buccal and lingual surfaces of the teeth. Special clamps, 
with large flanges, designed to clasp the roll or napkin and hold it 
firmly against the gums, may be had. Where this method of excluding 
saliva is efficient, the clamps are an advantage in that they permit 
the operator to use both hands. If the quantity of saliva delivered 
to the mouth is small, this method, in connection with the saliva 
ejector, may meet with success. 

The Exclusion of Saliva from the Mouth. — The older operators 
depended far more on the exclusion of the saliva from the mouth than 



158 EXCLUSION OF MOISTURE FROM TEETH DURING OPERATIONS. 

on its subsequent absorption. This may be accomplished by stopping 
the salivary ducts at the point where they open into the oral cavity. 
For this purpose, napkins from four to five inches wide and about 
twelve inches long, are desirable. These may be cut from a piece of 
clean, bleached linen and thrown away after use. The napkin should 
be folded longitudinally until it presents a width of an inch to an inch 
and a half. For operations on the right side below, the patient should 
be instructed to raise the tip of the tongue to the roof of the mouth and 
the napkin adjusted across the mouth from left to right, the end resting 
against the lingual surfaces of the teeth on the left side. The tongue 
tip is then lowered and the free end of the napkin carried from right to 
left over the dorsum of the tongue. Rolls or wads of absorbent cotton 
are then adjusted between the buccal surfaces of the upper molars and 
the cheeks, closing the openings from the parotid ducts. The fore- 
finger of the left hand resting on that portion of the napkin covering 
the dorsum of the tongue, is used to hold the tongue firmly against the 
floor of the mouth and the other ringers are used to hold the right cheek 
out of the way, the thumb being pressed firmly against the under part 
of the chin. If there is an excessive flow of saliva from the right parotid 
duct, the cotton covering it may be removed, when saturated, and a dry 
piece quickly and easily adjusted. This is, however, not often neces- 
sary. For operations on the left side below, the napkin is reversed, 
starting with the end resting against the lingual surfaces of the right 
teeth, passing under the tongue from right to left and over the dorsum 
from left to right. The forefinger of the left hand is now used to hold 
the left cheek away from the buccal surfaces of the teeth, while the 
other fingers depress the tongue and the thumb insures immobility 
by its position under the chin. 

Occasionally a patient will be found whose tongue involuntarily 
resists the effort to depress it but that ceases under firm, steady treat- 
ment. The napkin over the dorsum permits the operator to compel 
obedience from the tongue muscles that would be impossible with the 
bare fingers against the bare mucous membrane. By this method 
the secretion from the submaxillary and sublingual ducts is kept out 
of the mouth completely. Care must be exercised in removing the 
napkin for the mucous membrane dries so thoroughly it might be in- 
jured by roughness or haste. 

The difficulty in excluding saliva during operations on the upper 
teeth is much less. Here we only have the parotid duct to consider 
and the use of a napkin as described above under the head of the use 
of absorbents, is usually sufficient. It acts not only as an absorbent 



RUBBER CUPS, COTTON ROLLS AND NAPKINS. 1 59 

but also lessens the quantity of saliva delivered through the parotid 
duct. In some cases it may be advisable to also use the ejector. 

A form of tongue depressor consisting of a duckbill arm to rest on 
the dorsum of the tongue, a suitably shaped shield to rest against the 
under side of the chin, and a ratchet arrangement whereby the depressor 
may be locked when the relations between the tongue and shield are 
such that the tongue is fully depressed, may be bought of dealers in 
surgical instruments and Dr. Henry A. King, of New York, produced 
a similar device on lighter, more graceful lines, in 1904. If the patient, 
does not object to their use, these instruments permit of the use of the 
napkin, as described, with both hands free. 



CHAPTER X. 
PREPARATION OF CAVITIES FOR FILLINGS. 

BY A. E. WEBSTER, M. D., L.D. S., D. D. S. 

Definition. — Under this heading is included all those operations 
which have for their purpose the removal of carious tooth tissue, 
formation of cavities for the reception and the retention of fillings and 
the extension of cavity walls to prevent further decay. 

Nomenclature. — In every nation or class of people living and 
associating together is developed a system of signs or sounds by which 
ideas are communicated to each other. This is their language. In 
every business or trade or occupation there is similarly developed a 
system of signs, words and names which are used by those engaged in 
the same trade or occupation as a means of communication. These 
signs and names are termed the nomenclature of the trade or profession. 
Without such a code those in the same occupation w r ould not be able to 
understand each other. So in the subject of the preparation of cav- 
ities it is necessary to have a system of names and signs which all must 
understand before communication is possible. The majority of the 
names used in the preparation of cavities will be familiar to those who 
have studied dental anatomy. Others will be defined. The nomen- 
clature followed will be that adopted by the Institute of Dental Ped- 
agogics. 

Cavity Nomenclature. — Cavities in teeth take the names of the 
surfaces of the teeth in which they occur. 

Labial cavities occur in labial surfaces. 

Buccal cavities occur in buccal surfaces. 

Lingual cavities occur in lingual surfaces. 

Occlusal cavities occur in occlusal surfaces. 

Mesial cavities occur in the surfaces of the teeth looking toward the 
median line. 

Distal cavities occur in the surfaces of the teeth looking away from 
the median line. 

Proximal cavities are those which occur in the proximal surfaces 
of the teeth. 

Cavities which involve more than one surface take the name of the 
two or more surfaces involved, thus: 
ii 161 



[62 PREPARATION OF CAVITIES FOR FILLINGS. 

Mesio-occlusal cavities involve both the mesial and the occlusal 
surfaces. 

Disto-occlusal cavities involve both the distal and the occlusal 
surfaces. 

Mesio-labial cavities involve both the mesial and the labial 
surfaces. 

Mesio-lingual cavities involve both the mesial and the lingual 
surfaces. 

Disto-lingual cavities involve both the distal and the lingual 
surfaces. 

Mesio-occluso-distal cavities involve the mesial, occlusal and 
the distal surfaces. Other combinations may be made to describe 
the location of cavities. 

CLASSIFICATION OF CAVITIES. 

Teeth usually begin to decay in defects of the enamel surface or 
on smooth surfaces not kept clean. Thus they may be divided into 
two general classes; pit and fissure cavities, and smooth surface cav- 
ities. Pit and fissure cavities do not require to be extended beyond the 
limits of decay or the defect in the enamel, while those on smooth sur- 
faces usually require to be extended sufficiently to bring the margin 
of the filling to a point on the tooth's surface where it is kept clean 
either by the excursions of food or by the actions of the lips or 
tongue. 

Pit and fissure cavities occur in the lingual surfaces of upper in- 
cisors and occasionally in cuspids, and in the occlusal surfaces of 
bicuspids and molars and the occlusal and middle thirds of the buccal 
and the lingual surfaces of molars. 

The classification of cavities which follows requires a similar 
method of treatment for each class. 

Pit and Fissure Cavities. — Cavities in the occlusal and middle 
thirds of buccal and lingual surfaces of molars. 

Cavities in occlusal surfaces of bicuspids and molars and lingual 
surfaces of upper incisors and occasionally upper cuspids. 

Smooth surface cavities occur in the surfaces not kept clean and 
may be classified as to location as follows : 

i. Cavities in the gingival third of labial, buccal, and lingual sur- 
faces. 

2. Cavities in proximal surfaces of incisors and cuspids which do not 
involve the incisal angle. 



NOMENCLATURE OF THE INTERNAL PARTS OF CAVITIES. 163 

3. Cavities in the proximal surfaces of incisors and cuspids which do 
involve the incisal angle. 

4. Cavities in proximal surfaces of bicuspids and molars which do 
not involve the occlusal surface. 

5. Cavities in the proximal surfaces of bicuspids and molars which 
do involve the occlusal surface. 

NOMENCLATURE OF THE INTERNAL PARTS OF CAVITIES. 

The surrounding walls of a cavity take the names of those surfaces 
of the teeth toward which they are placed, thus an occlusal cavity has a 
mesial wall, a buccal wall, a distal wall, a lingual wall and a fifth wall 
which is known as the pulpal wall. 

The pulpal wall of a cavity is that wall which is occlusal to the pulp 
and at right angles to the long axes of the tooth. If the pulp be re- 
moved the floor of the pulp chamber becomes a wall of the cavity and 
is known as the sub-pulpal wall. In cavities occurring in the axial 
surface that wall covering the pulp is called the axial wall and if the 
pulp be removed the wall takes the name of the wall of the pulp cham- 
ber. Cavities in the axial surfaces of teeth have mesial and distal, 
or buccal and lingual walls, and an occlusal and a gingival wall, and an 
axial wall. 

In complex cavities which involve the axial and occlusal surfaces 
the gingival wall is termed the seat of the cavity and the pulpal wall is 
known as the step. 

For purposes of convenient description cavities in teeth are supposed 
to be cuboid in form. 

Where two walls join, a line' angle is formed taking the name of the 
two walls entering into its formation, thus: Bucco-pulpal line angle 
or gingivo-axial line angle. 

Where three walls join, a point angle is formed taking the name of 
the walls entering into its formation, thus: Gingivo-labio-axial point 
angle or gingivo-linguo-axial point angle. 

The enamel wall of a cavity is that portion of the wall between the 
cavo-surface angle and the dento-enamel junction and includes the 
thickness of the enamel. 

The dentin wall is that portion of a cavity which is lined with 
dentin. 

The enamel margin includes the whole outline of the cavity and is 
equivalent to the marginal line of the cavity. 

The cavo-surface angle of a cavity is the angle formed by the junc- 
tion of the wall of the cavity with the surface of the tooth. 



1 64 PREPARATION OF CAVITIES FOR FILLINGS. 

THE PLANES OF THE TEETH. 

The horizontal plane is at right angles to the long axis of the tooth. 

Mesio-distal plane is parallel with the long axis and passes 
through the tooth from mesial to distal. 

Bucco-lingual plane is parallel with the long axis and passes 
through the tooth from buccal to lingual. 

The bevel of the cavo-surface angle is reckoned from the plane of 
the enamel wall. 

DIVISIONS OF TEETH AND CAVITIES. 

For convenience of locating a cavity on the axial wall of a tooth 
the tooth may be divided into thirds, and known as the occlusal third, 
middle third and the gingival third. Cavities in teeth may be divided 
in the same way either in the horizontal plane or in the mesio-distal 
plane, thus: A buccal cavity is located in the gingival third, in the 
horizontal plane and in the middle third in the mesio-distal plane. 

STEPS IN CAVITY FORMATION. 

The beginner in any mechanical work does not at once arrive at the 
best and most expeditious methods of procedure. But after a time 
if he be an observing person he will fall into an order of procedure 
which he will follow more or less rigidly. Hence it is important that 
he should at first at least follow those who have had opportunities of 
developing the best methods. The Institute of Dental Pedagogics 
has given the following steps in cavity formation as those fulfilling 
the greatest number of requirements. 

i. Establish the outline of the cavity (outline form). 

2. Remove the softened decay. 

3. Give the cavity proper form. Which includes convenience form, 
resistance form and retentive form. 

4. Bevel and polish the enamel wall. 

5. The final touches or the toilet of the cavity should include a care- 
ful observation of the condition of the tooth tissue over the pulp and a 
thorough cleansing of the cavity surfaces. 

General Consideration of Outline Form. — Before a dentist is 
justified in undertaking the treatment of a patient's teeth for 
the purpose of eradicating present caries and the prevention of fu- 
ture decay he should consider well all the factors which enter into 
the causation of decay and its prevention. The family history and 
the personal history of caries are of value in deciding the character 
of the operations to be performed. In some families even though 



STEPS IN CAVITY FORMATION. 165 

there be many cavities while young, they yield to treatment and fill- 
ings have a degree of permanency not found in others of more favor- 
able appearance. Then again caries in some families rarely appears 
before the fifteenth year while in others it begins at the appearance of 
the deciduous teeth. Caries will cease at the twentieth year in some 
families and not recur until perhaps the fiftieth year or perhaps not at 
all. Patients giving a family history of immunity after a certain age and 
a personal history of immunity at the same age need not have what 
are sometimes called heroic operations done for them. The greatest 
attention in such cases should be given to the prevention of present 
decay rather than that which may occur in the future. 

Such conditions might influence to a large extent the location of the 
cavity margins. The physical, mental, and personal habits have a 
great influence on the character of operations that should be performed. 
Many patients apply for dental treatment who are not in a fit physical 
condition to have ideal dental operations performed. A dentist would 
be lacking in judgment who would ask a frail girl maturing into 
womanhood to submit to having the outline of many proximal cavities 
carried through sensitive tissue to bring them to a clearing margin. 
Then again there are those who are so weak mentally that it takes 
careful management to preserve their teeth at all. They think they 
cannot bear anything in the way of inconvenience. Such patients 
need the strong controlling force of a man who knows just how to handle 
them before he may venture to do ideal operations. 

Some patient's teeth are kept perfectly clean apparently without 
an effort. They eat proper foods and masticate them well, which is a 
factor in preventing caries. Almost all surfaces of the teeth are kept 
clean and are consequently immune to caries. If caries does occur the 
cavity margins do not require to be extended appreciably to meet 
areas which are immune. Others have teeth which always seem to 
have what might be called a scum over them, with cavities occurring 
in every defect of enamel and on surfaces which would be immune 
in other mouths. Where decay seems so progressive, cavity margins 
must be extended until they reach the immune areas of the tooth's 
surface even though much of the surface must be covered by filling. 

The very appearance of the mouth often helps the operator to 
choose the character of operation. A certain viscid tenacious saliva, 
abundant in quantity, usually indicates rapid decay and demands that 
the outlines of the cavity should be extended far beyond the areas of 
contact with the other teeth. Many points of white or yellowish- 
white decay on smooth surfaces especially in labial, buccal, and lingual 



l66 PREPARATION OF CAVITIES FOR FILLINGS. 

surfaces is indicative of a marked susceptibility and demands free ex- 
tension of cavity outlines, while if the cavities be dark brown or black 
in color and are found only in fissures the outlines need not be extended 
so freely. Because of the difficulty of keeping irregular teeth clean 
cavities in such cases should be extended fully. It resolves itself in- 
to this, in all cases where decay occurs, that part of the tooth's surface 
which is not kept clean about the cavity should be included within its 
outline. 

i. The outline form is the form of the area of the tooth's surface to 
be included within the outline of enamel margins of the finished cavity. 
The first step in the preparation of any cavity is to decide as far as 
possible the extent of the caries which in a measure helps to locate the 
outline of the cavity. The extent of the caries helps to locate the outline 
only in simple pit cavities, and those occurring in exposed surfaces and 
those which are so large as to have involved all the defects of enamel 
and susceptible areas of the tooth's surface under consideration. To 
find out the extent of the caries it is necessary to break down the 
enamel not supported by dentin except perhaps where it may be left 
for esthetic reasons as in labial and buccal cavities in incisors, cuspids 
and bicuspids. The loosened and soft decay may be removed and the 
cavity washed out with a stream of tepid water. This will so clear 
the field of operation that a better judgment can be made as to the 
amount of sound tissue remaining, the condition of the pulp and the 
proper location of the outline. In the further preparation of the cavity 
it is well to have the rubber dam in position or use some other means of 
keeping the cavity dry. » 

(a) In fissure cavities the outline must include all the fissures 
and angular grooves radiating from the caries even though the cavity 
be but small. Such a cavity usually begins because of a defect in the 
continuity of the enamel surface and if only the carious portion be re- 
moved and a filling inserted the defective fissures remaining are just as 
likely to decay as originally. It is found that unless filling materials 
are polished flush with the enamel surface the thin edge left over the 
margins will likely be a point of leakage and later decay. If angular 
grooves are left radiating from a cavity it is impossible to so polish the 
filling that none will be left over these margins, hence it is better to 
cut them out and include them in the cavity. 

(b) Superficial defects of the enamel about cavities should be 
cut out until sound enamel is reached and in some cases until full 
length rods are reached. In many cavities occurring about the gum 
margins there is an area of whitened or defective enamel passing around 



STEPS IN CAVITY FORMATION. 167 

the tooth which if not cut out and included in the cavity will decay in 
a short time and cause the loss of the filling, and perhaps the confi- 
dence of the patient in filling operations. In some of these cases the 
outer ends of the rods are worn away or lost by the effects of superficial 
decay and are likely to cause the failure of the filling if the margin pass 
across it. 

(c) Extension for Prevention. — The general rule laid down 
for locating the margins of cavities which occur in proximal surfaces 
is to extend them to such a point on the tooth's surface that the joint 
between the filling and the enamel may be in immune areas. There 
may be some exceptions to this rule in rare cases but if cavity margins 
are allowed to come against adjoining teeth the fillings cannot be con- 
sidered more than temporary. 

Any one who has practised dentistry for more than a few years 
cannot help having observed the wisdom of extending all proximal 
cavities buccally, lingually, and gingivally far enough to bring the 
margins to such a point on the tooth's surface as will ensure their being 
kept clean or protected by healthy gum tissue. It makes but little 
difference whether the cavity be small or large in a proximal surface 
the outline should be well beyond any contact with the adjoining tooth. 
This extension of cavity walls through sound tissue to bring the margins 
to immune areas is known as extension for prevention. 

(d) A developmental groove or another cavity should not be 
allowed to come too close to enamel margins. It is better in such 
cases to cut out the groove and include it in the cavity. The rods of 
the enamel in such cases usually stand at right angles to the surface 
which is faced away from the cavity, so when the cavity is prepared 
they are left without support. If only a small portion of enamel be 
left between a cavity and another filling it is almost certain to become 
a source of weakness to both fillings. Such enamel is usually more or 
less undercut and unsupported by dentin and the seat of fracture 
during the insertion of the gold. 

(e) The buccal and lingual margins of proximal cavities in bi- 
cuspids and molars should be as nearly parallel as possible and at right 
angles to the seat of the cavity. Such a preparation makes the gin- 
gival wall more accessible to start and condense the first portion of the 
filling. Besides it brings the outline into full view during the building 
of the filling. If these margins and the walls of the cavity adjoining 
them are parallel the filling material as it is condensed will not draw 
away from the margins as in divergent walls, or tend to fracture the 
tooth as in convergent walls. 




l6S PREPARATION OF CAVITIES FOR FILLINGS. 

(f) The outline in all cavities should be straight tines or regular 
curves because it is much easier to adapt a filling material to a regular 
margin than to an irregular or ragged one. Besides they are said to 
be more esthetic, which is doubtful, but at all events they look more 
like the work of a good mechanic. 

Technique. — To obtain the proper outline of a cavity it is nec- 
essary to break down and remove all enamel not supported by dentin. 
The straight chisel in the hand well guarded against slipping will cut 
away enamel readily if the edge of the blade is made to insinuate itself 
between the rods. The force should be applied in the 
direction of the long axis of the rods. In some cases the 
sharp edge of the blade may be placed against the wall of 
enamel and the edge snapped of! piece by piece (Fig. 113). 
In others the edge of the chisel may be placed against the 
enamel and given a quick decisive blow with a mallet 
which will readily fracture the enamel (Fig. 114). It is 
well to be careful not to attempt to cut off more at once than will easily 
be cleaved away on account of the shock from the mallet which may 
be painful to the patient and come with such suddenness as to cause 
doubt of the operator's skill. A chisel in the automatic mallet will 
often break enamel, but like hand pressure it is difficult to control. 
A chisel in an engine mallet will break enamel rapidly and is under 
control but violent on the patient if a blow is given against the enamel 
which does not chip off. The final planing of the enamel wall to bring 
it to evenness must be done wjth a chisel. Cavities in proximal sur- 
faces which require extension through sound tissue are 
best enlarged by cutting the dentin out under the enamel 
with a comparatively small bur and then breaking down 
the enamel with the chisel. 

Fissure cavities can be extended in undecayed enamel 
by cutting a narrow slot through the groove with a small 
dentate fissure bur ground at the point on two sides to IG " II4 ' 
make it into a drill. A wornout, inverted cone bur ground to the 
same form will cut equally well. If the hand-piece be given a 
swaying motion and the point kept sharp even perfect enamel can 
be cut rapidly. If it be found that the dentin is not very sensitive 
the drill point may be directed rather under the enamel which seems 
to undermine it and allow it to cut easier. It is important that the 
drill be small, a large drill imparts too much jar to the tooth. Even 
the smallest size of an inverted cone bur so ground will serve even- 
purpose because once the enamel is broken the edges may be chipped 




STEPS IN CAVITY FORMATION. 1 69 

in with a chisel or a hatchet excavator. In certain large distal cavities 
in molars the buccal and lingual walls cannot be reached with a 
straight chisel and a curved chisel with a narrow blade cannot be con- 
trolled if force enough be applied to fracture the enamel. The blade is 
almost certain to drop into the cavity and touch sensitive dentin or per- 
haps wound a living pulp. An instrument made on the form of a 
broad axe, with the blade short and wide and parallel with the long axis 
of the -shaft will successfully break such enamel walls without danger 
to the pulp or the gum tissue. 

In smooth surface cavities in exposed positions the outline may be 
extended with dentate inverted cone burs by placing the base of the 
cone against the axial wall and carrying the corner of the bur under 
the enamel. In this way the foundation of the enamel is cut first 
leaving it easily cleaved away. 

The final trimming or planing of the enamel wall is done with broad 
bladed chisels holding the width of the blade parallel with the long 
axis of the rods. Black's side instruments will shave the buccal and 
lingual enamel walls of molars, while the gingival is best reached with a 
Darby-Perry chisel. The enamel walls of pit and fissure cavities are 
best trimmed with fissure burs run rapidly and held at right angles to 
the pulpal wall. 

2. Softened and decalcified dentin should next be removed from the 
cavity. In certain rare cases a portion of hard, discolored dentin may 
be left when its removal would expose a living pulp. In such cases a 
non-irritating disinfectant should be used for sufficient length of time 
to insure disinfection before the filling is inserted. 

Technique. — The manner of removing the remaining decayed 
tissue depends upon the character of the tissue, the size and location 
of the cavity and the sensibility of the dentin. In shallow cavities in 
exposed surfaces where the dentin is usually sensitive a deep decisive 
cut with a hatchet excavator in one corner of the cavity, followed by 
prying up or scooping out of the tissue in one layer is less painful than 
to attempt to remove the tissue in small pieces. In large cavities 
when the decay reaches close to the pulp it is better to go around the 
edges with spoon excavators flaking up the decay and peeling the 
layers off without making much pressure. After the decayed tissue 
is well removed down to the solid dentin at all points except where 
the pulp comes nearest to the cavity, then take a large spoon excavator 
and carefully scrape away the decalcified dentin until hard tissue is 
reached. This can be done without pain to the patient if little or no 
pressure is applied. Usually in these cavities it is the dentin at the 



170 PREPARATION OF CAVITIES FOR FILLINGS. 

dento-enamel junction which is most sensitive. In certain cavities 
of dark brown or black decay where the tissue is hard, as occasionally 
occurs in occlusal cavities in molars in old patients, the decay may be 
most rapidly removed with burs. In no case should burs be used 
close to the pulp. In fact burs are of little or no value in removing 
decayed tissue except where it is hard. Spoon excavators are of most 
general use, though hatchets and burs may be used in special cases. 

3. A cavity may be considered of proper form when it is so shaped 
that it can be conveniently filled, when it will retain the filling and 
when its walls will resist any stress w T hich may come upon them. 

(a) For convenience a cavity should be so formed that all its walls 
may be seen directly or brought into view with the mouth mirror. 
Grooves and undercuts should be avoided in a completed cavity form. 
They are always difficult to fill and add very little to the retention of 
the filling, and are a source of weakness to the walls. Line angles 
and point angles should not be so small and acute that instruments 
cannot reach their depths. Proximo-occlusal cavities in molars 
and bicuspids are in their most convenient form for filling when they 
are so shaped that they will retain the filling and resist the stress of 
mastication. If such cavities have a flat seat and step, parallel buccal 
and lingual walls and a dovetail in the occlusal surface, they are then 
convenient to fill with whatever material is desired. Cavities in 
incisors and cuspids require perhaps some slight modification of a 
gingivo-labio-axial point angle and gingivo-linguo-axial point angle 
to make it possible to more conveniently start a gold filling. These 
angles are made more acute and the corner is cut more deeply than 
is necessary for retention. They may be truly called convenience 
angles. In some cavities difficult of access it is often more convenient 
to cut away a wall or to extend an outline so as to bring the walls into 
full view. The labial surfaces of incisors and cuspids should not be 
cut away for convenience of access to a small proximal cavity. In 
the majority of these cases it is better to separate the teeth until access 
can be had to properly prepare the cavity and insert the filling, while 
in other cases the lingual surface may be cut into for convenience of 
access. 

Technique. — The general technique of obtaining the outline form 
having been described it is not necessary to discuss more than what is 
specially done for convenience. A cavity with a good outline is easily 
filled. In many cavities having penetrating decay it will often be more 
convenient to fill any irregularities or pits not used for retention with 
cement, leveling up the walls. Often a buccal plate of enamel in a 



STEPS IN CAVITY FORMATION. 171 

mesio-occlusal cavity in an upper bicuspid is left for appearance 
sake though the dentin is gone from beneath it. The loss of the 
dentin leaves such a deep groove at the junction of the axial and buccal 
walls that it is very inconvenient and difficult to fill it with gold. In 
such cases it is much better to fill the grooves with cement and square 
up the buccal and lingual walls so that they may be parallel. For 
convenience of starting a cohesive gold filling in proximal cavities 
in incisors and cuspids a No. J or No. 1 inverted cone bur, which is 
held parallel with the long axis of the tooth as it is carried from labial 
to lingual to form a flat seat for a filling, may be swayed toward the 
labial as it is carried to the labio-gingivo-axial angle, and as the bur 
approaches the depth required it should be swayed to the lingual and 
carried slightly toward the incisal. By this movement a deep acute 
angle is cut which has the general direction of the greatest amount of 
tooth tissue avoiding the pulp. This acute angle is in a like manner 
cut in the gingivo-linguo-axial angle. With acute angles cut in 
opposite walls in the seat of any cavity there should be no difficulty 
in starting a cohesive gold filling. These may be truly called con- 
venience angles though they are large enough to assist in the retention 
of the filling. These angles are easily filled and securely hold the gold 
in position while more may be built upon it. The small pits drilled 
at random in the seat of the cavity as has been too often the practice 
are difficult to fill and not always secure when filled. There seems 
to be a growing tendency among operators who do not wish to expose 
gold on labial surfaces to cut the lingual surface freely away, making 
a dovetail in the enamel for retention. This is really a convenience 
form. 

(b) Resistance form is that shape given a cavity intended to 
afford such a seat for the filling as will best enable it to withstand the 
stress brought upon it in mastication. Its importance depends upon 
the area of the surface of the filling exposed to occlusion, and the 
strength of the closure of the jaws. The general rule in foundation 
construction is to keep as nearly a fat base as possible. Foundations 
made to resist heavy weights and tipping stress are flat. A cone- 
shaped base in a pulpless bicuspid or molar decayed mesio-occluso- 
distally has often been the cause of a fracture of the root. In such 
cases the filling acts as a wedge, cleaving the weaker wall. The seat 
of occlusal cavities should be flat and at right angles to the stress 
coming upon it, likewise cavities in proximo-occlusal surfaces of 
molars and bicuspids should have a flat seat and step to resist the 
heavy stress of occlusion and the tipping stress which comes upon 



172 PREPARATION OF CAVITIES FOR FILLINGS. 

these fillings. It is not often realized by operators how much stress 
some fillings may be called upon to resist. In strong men a single 
molar may occasionally have a force of from two hundred to two 
hundred and fifty pounds applied to it. The closure of incisors of 
course is much less, but the anchorage for a filling in these teeth is less. 
The biting off of a crust of bread and its mastication will involve a 
pressure of from 100 to 150 lbs., while an ordinary beefsteak requires 
seventy-five pounds of pressure on an area the size of the human teeth 
to cut through it. In accidents of a piece of lead in canned goods, 
or shells or bones in flesh, a filling may receive the whole weight of the 
closure. Pulpless teeth, crowns and dentures have much less force 
applied to them than normal teeth. It would seem that when the 
pulp of a tooth is lost the pericemental membrane loses some of its 
power to resist pressure without injury. Hence fillings antagonizing 
with pulpless teeth crowns and dentures need not be so securely seated 
as those opposing sound teeth. In deciding what amount of seating 
a filling should require the force of the closure of the jaws must be 
well studied. Also the teeth antagonizing the filling and the area 
of the filling exposed to occlusion. It is obvious that labial, buccal, 
lingual, and small proximal cavities in incisors and cuspids do not 
require to be securely seated because the surfaces of these fillings 
are not exposed to the forces of mastication. No one thing has 
done more for the stability of fillings than the study of the forces of 
the closure of the jaws and^the introduction of proper methods of 
seating fillings to resist that force. 

Technique. — The inverted cone bur, the fissure bur, the chisel, 
the hatchet and the hoe excavators are the only instruments which 
can be used to form a flat seat in cavities to resist the force coming upon 
the filling. Round burs and spoon excavators have no place in form- 
ing the seat of a cavity. The seat, the step, and the lateral walls 
must be definite, joining each other with right angles or acute angles. 
The seat in molar and bicuspid cavities may be cut flat from buccal 
to lingual and from the enamel margin to the axial wall with an in- 
verted cone bur about one millimeter in diameter. As this bur is 
carried back and forth from buccal to lingual there is often some 
difficulty in keeping it from jumping out of the cavity, and perhaps 
winding up the septum of rubber dam between the teeth, or wounding 
the gum, or perhaps cutting dangerously near the pulp. The diffi- 
culty of holding a bur in such a position is increased with the increase 
of the size of the bur and also by placing it in the right-angled hand- 
piece. If, after all the overhanging enamel is broken down and the 



STEPS IN CAVITY FORMATION. 1 73 

softened decay removed, the Ivory or Hinicker matrix be adjusted, 
a bur can then be held in the base of the cavity without fear of accident 
in one direction at least. It is generally well to use a small bur, 
cutting the dentin only, and then cut away the enamel with Black's 
side instruments or Darby-Perry chisels. This will leave a wide 
flat seat. The step is usually partly formed with cement and as 
the last part of its formation an inverted cone bur in the right angle 
may be carried over the whole step. The seat of incisor cavities is 
formed in the same way only using much smaller burs; about a half 
millimeter inverted cone is more suitable for laterals and some centrals. 
(c) Retention form is that shape given a cavity which will prevent 
the filling from being dislodged. This is largely provided for in the 
resistance form and to some extent in the convenience form, but in 
certain cavities the filling might resist the direct stress upon it and yet 
be easily displaced with slight lateral force. Retention form is pro- 
vided for in proximo-occlusal cavities in molars and bicuspids by a 
dovetail in the occlusal surface and by providing parallel walls or 
perhaps walls slightly undercut. Proximal cavities in incisors and 
cuspids which do not involve the incisal angle do not need more than 
a flat seat deepened at the gingivo-labio-axial and gingivo-linguo- 
axial angles, with a slight undercut at the junction of the labial and 
lingual walls at the incisal. Cavities which involve the incisal angle 
should be provided with a step if much stress is to come upon the 
fillings. For many years operators have been chiefly concerned in 
the retention of fillings, only having regard to what might tip them 
from the cavity, not thinking that the greatest force in dislodging 
fillings is the direct stress of the closure of the jaws. The more fillings 
failed the more and the deeper were made the pits, grooves and under- 
cuts. The pits did not contain enough filling material to have strength 
to resist the stress, and the grooves and undercuts often cut clear 
through the dentin, leaving only the enamel for retention which 
frequently fractured. The thoughtless operator has an idea that if 
he uses a large round bur in the center of the tooth making the cavity 
larger inside than at the margins the filling cannot get out. This 
might succeed if the enamel were not so friable when unsupported 
by sound dentin. The surest way to make a cavity which will retain 
a filling is to study carefully the forces which may come upon it to 
dislodge it. Estimate the strength of the cavity walls and then so 
shape the cavity that its seat or foundation will be opposite the stress 
applied and its retention cut in the direction of the greatest amount 
of dentin, and if undercuts are used place them in opposite walls of the 



174 PREPARATION OF CAVITIES FOR FILLINGS. 

cavity. In general the retention should be as near the point of stress 
as possible, and the area of the seat and step equal to the area of the 
tilling exposed to the occlusion. 

Technique. — A cavity is usually shaped to resist tipping stress 
with the same instruments as are used to make the resistance form. 
Occlusal cavities in molars and bicuspids require parallel walls, and 
at opposite points a slight undercut which can be made with the inverted 
cone bur as its shaft is held at right angles to the pulpal wall. The 
only force which might remove this filling would be a lifting force 
from the adhesion of some sticky substance -such as taffy. Proximo- 
occlusal cavities in molars and bicuspids cannot be retained to any 
extent by grooves or undercuts. The dovetail in the occlusal surface 
which is easily cut with a cross cut fissure bur or inverted cone bur 
is all that is necessary. In some bicuspids retentive form may be 
obtained in the occlusal surface by deepening the step at the point 
farthest from the proximal cavity with an inverted cone bur slightly 
undercutting the buccal and lingual walls. Proximal cavities in 
incisors and cuspids may have grooves extending out from the point 
angles for retention. As the inverted cone bur is sunk into the angles 
it may be carried up the labial and lingual walls a short distance 
making a groove. In many of these cases an obtuse angle hatchet 
or hoe may be used to cut a definite angular groove in these w T alls. 
The retention towards the occlusal is best cut with a small contra- 
angled hatchet excavator. No. 27, S. S. W., is a very suitable size. 

4. The proper bevel and polish oj the enamel wall of a cavity 
is of prime importance because the permanency of the filling depends 
so much upon the joint between the filling and the tooth. A good 
working knowledge of the histology of the enamel is essential to 
obtain the correct bevel of the enamel wall at all points. 

The enamel is composed of rods cemented together by a less dense 
substance than that composing the rods. In consequence of the cement- 
ing substance being less strong than the rods the structure is likely 
to cleave between the fibers. The rods are difficult to cut across or 
hard to wear down from their ends but easily split, if the cleaving 
force is in the direction of the long axis. This is of importance in 
breaking down enamel to open into a cavity. If a chisel be directed 
against the enamel so that the rods are split apart little force is re- 
quired. The rods are more or less parallel in their outer half 
while in their inner half they are interlaced and tangled together. 
In some teeth the rods radiate from the dentin almost parallel, while 
in others they are wavy and are interlaced a great deal. It is this 



STEPS IN CAVITY FORMATION. 1 75 

variation in the interlacing of the fibers that accounts for the difference 
in the degree of resistance enamel has for cutting instruments. It was 
formerly believed that enamel which was very resistant to cutting 
instruments was harder because it contained more lime salts than 
that which cut more easily. This was shown to be a fallacy by Dr. 
Black, who demonstrated that the so-called soft teeth had not less 
lime salts but seemed to be soft because the enamel rods were straight 
and consequently easily split apart, while the so-called hard teeth 
were merely hard because the fibers of enamel were interlaced and 
tangled together much like the fibers of wood in a pine knot, and any 
attempt to cleave them is difficult because no matter in what direction 
the attempt is made the rods must be cut across. 

The direction of the enamel rods may be said to be from the center 
of the tooth to the surface. The rods are generally perpendicular 
to the surface but there are many locations w T here they approach the 
surface at a decided inclination. At a line about the center of a 
molar or bicuspid the rods are perpendicular to the surface, but as the 
occlusal surface is reached the rods become more and more inclined 
toward the cusps where they become parallel w T ith the long axis of the 
tooth and perpendicular to the tip of the cusp. Likewise as the gingival 
is reached the rods become more and more inclined toward the root. It 
is clear from these facts that a cavity in an axial surface coming close 
to the cusp or marginal ridge cannot have its occlusal wall perpendic- 
ular to the axial surface without leaving many enamel rods not sup- 
ported by dentin. A decided bevel should be given enamel walls 
at these points which may make the filling material so thin that it 
may flare up from the margin. Any attempt to make an occlusal 
wall of a cavity close to the occlusal surface is fraught w T ith many 
chances of failure. It is usually advisable to cut through to, and 
include some of the occlusal surface. 

The enamel rods incline toward pits and fissures and as they pass 
from a fissure in the occlusal surface of a bicuspid or molar toward 
the cusps, the rods incline more and more until they are perpendicular 
to the tip of the cusp. Thus a groove or fissure which is not cut out 
very widely requires only parallel walls to protect its margins, while 
a cavity in the occlusal surface of a bicuspid which is cut widely 
enough to approach the cusps needs a good deal of bevel. 

In incisors and cuspids a line around the crown at the junction of 
the gingival with the middle third will find the rods pretty generally 
perpendicular to the tooth's surface. But as the incisal is reached 



176 PREPARATION OF CAVITIES FOR FILLINGS. 

the inclination of the rods becomes greater and greater until they 
reach the cutting edge where they are parallel with the long axis of 
the tooth. The inclination in the incisal third is often as much as 
30 to 40 degrees. In proximal surfaces the degree of inclination of 
the rods depends upon the abruptness with which these surfaces join 
the incisal edge. The more rounded the corner the more the rods 
are inclined toward the incisal. Thus on the distal surfaces of laterals 
the inclination is greater than on the mesial surface. Proximal cavities 
co ming close to the incisal edge in these teeth require so much bevel 
to remove the short rods that the margin of the filling is endangered 
by being too thin. 

Passing around the incisors and cuspids the rods are generally 
perpendicular except at the junction of the proximal and lingual 
surfaces, where the rods are inclined towards the marginal ridge and 
become rapidly inclined the opposite way on the lingual, and con- 
sequently when this ridge is approached it should be cut well back 
because the rods are not supported. 

Cavity walls cut in the incisal surface of incisors and cuspids 
are well protected even though not brought down on the labial or 
lingual surfaces because of the inclination of the rods. 

Since the enamel rods are not always parallel with each other nor 
always at right angles to the plane of the tooth's surface, and since 
all rilling materials are npt always of equal strength with the enamel, 
it is not advisable to make the cavo-surface angle a right angle. But 
instead the outer half of the enamel wall should be cut back until 
the angle formed by the junction of the enamel wall and the tooth's 
surface should be greater than a right angle. The number of degrees 
greater depends upon the inclination of the enamel rods, the friability 
of the enamel, the force to come against it and the kind of filling 
material to be used. Gold fillings have the greatest protecting power 
for enamel walls and are the most likely to cause fracture or crumbling 
of the edge during insertion, consequently cavities prepared for the 
insertion of gold require more bevel than those prepared for amalgam 
or porcelain. Cavities prepared for gold, where much force may 
come upon the edges and the enamel is friable, require more bevel 
than cavities which occur in surfaces where less force may fall. Teach- 
ers and writers of operative dentistry have always said much on 
beveling enamel walls but rarely given the student any adequate 
idea of how much bevel a wall should receive. This idea is hard to 
impart in words unless accompanied with diagrams and a statement 
of the number of degrees. Every student has an idea of what a right 



STEPS IN CAVITY FORMATION. 1 77 

angle is, and he knows when a cavo-surface angle is a right angle. 
Xow if he will divide a right angle into sixteenths, eighths, sixths, and 
fourths he will have an idea what is meant when the bevel is to be 5 to 
25 degrees. This means that the cavo-surface angle is 90 degrees 
plus the number of degrees of bevel (which is for example 25) or 115 
degrees. As a rule when a lecture is given to a class of students 
on beveling enamel walls there will be many of them go to the extreme 
in bevels. This must be guarded against lest the filling material 
be too thin on the edge. 

Technique. — Beveling and smoothing enamel walls require so 
much skill and deft manipulation that it is only after repeated trials 
in cases where the results can be examined with a large magnifying 
glass that an operator can be at all sure of results. 

A disk is the most suitable instrument to bevel and polish enamel 
walls but unfortunately its range is limited. There are really but few 
cavity walls which can be reached at the proper angle with a disk. 
It will reach the labial, lingual and buccal enamel walls in large proxi- 
mal cavities but not the gingival, and only occasionally the occlusal. 
The beginner is certain to round the cavo-surface angle with a disk 
unless he bears in mind that the disk must not be pressed against the 
wall, but must be held in position to cut the rods parallel with their long 
axis, allowing no wabbling of the hand-piece, mandrel or disk. When 
the rods are thus cut the hand -piece is held at the necessary angle to 
cut the bevel required. Often too much bevel is cut in large proximal 
cavities, by allowing the disk to go too close to the gingival wall. At 
the junction of the gingival wall with the proximal walls the rods are in 
such a direction that the disk cannot possibly reach them to give them 
the proper bevel. The gingival enamel wall must be trimmed and 
beveled with a bur or chisel. A disk in the right angle will reach en- 
amel walls in molars and bicuspids to better advantage in many cases 
than the straight hand-piece. 

The next most suitable instrument and the most universally applic- 
able is the chisel. As the walls are planed down parallel with the 
long axis of the rods they may then be shaved down to the proper 
bevel. The instrument must be held firmly and not allowed to turn 
or catch and jump as it is carried along the enamel wall. 

The bur is very universal in its application in trimming and beveling 
enamel walls but can never leave as smooth and uniform a margin as 
the disk. In all small cavities in pits and fissures, and in labial and 
lingual surface cavities it is the only instrument that can be used. 
In the majority of such cavities the walls are cut back with a bur as 



1 ;S PREPARATION OF CAVITIES FOR FILLINGS. 

the cavity is being prepared. The bevel may be made with a straight 
cut fissure bur run rapidly. The gingival enamel wall in proximal 
cavities may be best trimmed with a round bur, and it is recommended 
by Johnson for trimming the walls in occlusal cavities in molars and 
bicuspids. 

The strip has a very limited use in smoothing enamel walls. It 
may be used in proximal cavities in incisors which do not involve the 
incisal edge but extend well onto the labial and lingual surfaces. In 
this position a strip held tight and passed back and forth from labial 
to lingual without allowing it to be lapped around the tooth will smooth 
the margin as nothing else will. 

5. The toilet or putting the final touches on the prepared cavity 
should include a close scrutiny of the condition of the tissue covering 
the pulp and removing any dust or chips which may have collected in 
the cavity. 

If the cavity wall be at all close to the pulp it is well to go over it 
with a large, sharp spoon which will remove any remaining de- 
calcified dentin. Some care is needful lest so much pressure be applied 
as will cause pain. It is usual to cover such a pulpal or axial wall 
with cement and then form this up as if it were a wall of dentin. The 
cavity may now be dried thoroughly from a blast of warm air which 
will remove loose chips, but if moisture has been allowed in the cavity 
some of the chips will* be so attached to the walls and crevices that 
they will not be removed by a blast of warm air. In such cases a 
piece of dry cotton rubbed around the walls will loosen the debris and 
then it can be blown away. Alcohol is often used to assist in drying 
a cavity but in sensitive teeth the patient receives a shock from the 
rapid evaporation of the alcohol. 

INSTRUMENTS. 

While it is of importance to know how to prepare a cavity it is of 
almost equal importance to know what instruments to use and how 
to use them. The study of instruments and how to use them is no 
small part of the preparation to practise dentistry. We are known 
by our tools. A fifteen minutes' examination of a dentist's operating 
equipment should satisfy any one as to his standing as an operator. 
Our instruments are of such importance to us that they deserve much 
of our attention in selection, arrangement and keeping in order. 

An instrument is divided into handle, shank, blade and cutting 
edge. (Fig. 115.) 



II 



INSTRUMENTS. 179 

The handle is that part which is grasped while the instrument 
is being used. 

The shank is that part connecting the handle with the working 
point or cutting edge. 

The working point or cutting edge is that part of the in- 
strument which comes in contact with the material worked upon. 

If the working point be flat and sharp the portion widened 
to bring out this form is called the blade. 

For convenience of communication instruments are classi- 
fied as excavators, pluggers, scalers, trimmers, separators, 
polishers, clamps, burs, drills, burnishers, etc. These names 
denote the purpose or the use of the instrument. If we wish 
to further describe an instrument we say " hatchet " or " spoon " 
excavator, "right angle," "contra angle,' 1 or "cow horn" 
plugger. These refer to the form of blade or shank. 

Chisels which are used for cutting or chipping away 
enamel have their cutting edges at right angles to the shaft 
and are sharpened by cutting or grinding only one plane of 
the blade. 

Hoes have the cutting edge at right angles to the shaft 
but the shank is so bent that the edge is looking towards the 
opposite end of the shaft, and the bevel to form the cutting 
edge is at the expense of that part of the blade away from the 
handle. They are used only with a drawing motion. 

Hatchets have the cutting edge parallel with the long axis 
of the shaft and the cutting edge is formed by cutting or grind- 
ing both planes of the blade. The shanks are made at various 
angles to bring the edge within reach of the cavity walls. 

Spoons are really not spoons in the true sense of the word. 
At one time they were made that they would dip up fluid but 
they are not now so made. There is no concavity in the 
blade. They have shanks of various curves to make the 
blades reach into the various depths of cavities. Spoons are, 
with the chisel, the most useful instruments in our equipment. 
They will remove softened decay to best advantage and will 
also cut decalcified dentin. 

There are gingival margin trimmers and side instruments 
which are modifications of the chisel with shanks formed so 
as to bring the working edge into positions where the ordinary chisel 
will not reach. 

While it is desirable to have everv form and varietv of instrument 






i So 



PREPARATION OF CAVITIES FOR FILLINGS. 



that will assist in any way in operating, it is at the same time desirable 
to have as few instruments as will fulfil the requirements. It will be 
found that the most useful instruments for all cavities in molars and 
bicuspids will be chisels, spoons and burs, while incisors will demand 
the small hatchets in addition. 

Below is an equipment of cutting instruments sufficient to begin 
with and will fill most requirements. (Figs. 116 to 140.) 



Figs. 116 




Figs. 128. 129. 130 



i35- i3 6 - 



- THE DENTAL ENGINE. 

The dental engine is classified as an instrument used in the prep- 
aration of cavities. While it may not be used to any extent in the 
preparation of a given cavity yet it is indispensable to the up-to-date 
operator. Other things being equal the operator who uses the dental 
engine the least will please his patients the most. The dental engine 
should only be used for that part of the preparation of a cavity which 
cannot be conveniently done by hand. If such a rule were followed 
in practice patients would not dread dental operations. There are 



I 



BURS. 



181 



two general forms of engines which affect operations to a marked 
extent, the all cord engine and the flexible cable. The all cord engine 
carries the bur forward without any jar or shock, while the flexible 
cable usually winds up or springs back as pressure is brought upon 
the instrument, thus the bur is rotated with a series of stops and rapid 
turnings which jar the tooth and unnerve the patient. The all cord 
engine is not so convenient to reach difficult locations hence its want 
of popularity. 

BURS. 

Only small burs should be used in the cable engine; those more 
than one and a half millimeters in diameter should not be used in 
teeth with living pulps or those with a sensitive peridental membrane. 
There are many forms of burs and drills used in cavity formation but 
the most useful is the inverted cone. (Fig. 141.) The round bur which 






142. 



143- 



144- 



145- 



has been used so extensively has no place in cutting that part of the 
cavity where a bur is indispensable. A bur should never be used to 
remove softened decay because spoon excavators will do it better. 
The round bur and the cone bur are useful to open into a pulp chamber 
when the pulp has been desensitized or devitalized. (See Figs. 142 
and 143.) The form of the blades of a bur has something to do with 
the rapidity of its cutting. The dentate bur cuts enamel more rapidly 
than the plain blade. There is a dentate pear-shaped bur that cuts 
enamel better than any other form. (Fig. 144.) 

The inverted cone bur has the great advantage of being capable 
of being made into other forms which are as useful as the original. 
Burs cannot be sharpened to make it pay at present prices but the 
operator can in a moment convert a dull bur into a most useful instru- 
ment for cutting out fissures or drilling out old fillings. A bur which 
has once cut enamel should never again be used to cut sensitive dentin. 
It has lost its keen edge. Burs should be arranged in the bur rack as 
new ones, those used on dentin a few times, those used on enamel and 
those only useful to grind into drills, etc. Dull fissure burs can be 



[82 



PREPARATION OF CAVITIES FOR FILLINGS. 




flattened on opposite sides and the end sharpened into a drill point. 
g. 146.) Dull inverted cone burs may be ground square across 
the end, thus cutting the blades off the end and bringing them far 
enough up the shaft to be sharp. This instrument will often cut out 
fissures as well as the original bur. It can be ground in this way 
until the blades are all ground off. (Fig. 147.) 
The old inverted cone may be ground into 
wedge or hatchet shape at the end (Fig. 148) 
and used to open up fissures, but such an in- 
strument unless small gives the tooth quite a 
shock. It cuts better if the hand-piece is given 
a swaying motion. 

SHARPENING OF INSTRUMENTS. 

No instrument which is intended to cut 
sensitive dentin should be used until it is first 
sharpened. Because a hatchet is new, it is no 
guarantee that it is sharp though it is likely to 
be. An Arkansas stone, on account of being 
Figs. 146. 147. 148. fine and hard, is the most suitable for sharpen- 
ing dental cutting instruments. If the stone 
is soft the fine instrument will sink into it, cutting it into gutters, or 
will catch and spoil the cutting edge. The stone should be wiped off 
with an oiled rag and thus kept free from particles of steel. After 
spoon excavators have been sharpened for some time on the Arkansas 
stone they develop what is called a thick edge and should be ground 
thin on a carborundum wheel, care being taken not to heat so fine a 
point while grinding it. 

The first attempts at sharpening chisels and hatchets may result 
in improper bevels, but some attention to this point will avoid the diffi- 
culty. A free back and forth movement of the hand will ensure best 
results. Spoons are the most difficult to sharpen. The motion should 
be back and forth on the stone, keeping the cutting edge parallel with 
the motion, and during each stroke the instrument is rotated so that 
every part of the edge will come against the stone during the motion. 

PREPARATION OF PIT AND FISSURE CAVITIES. 

General Conditions. — Pit and fissure cavities are the result of 
defects in the enamel covering of the tooth, and are to be found in the 
occlusal surfaces of bicuspids and molars, lingual surfaces of incisors 
and occasionally in the occlusal third of the buccal surfaces of molars. 



PREPARATION OF PIT AND FISSURE CAVITIES. 1 83 

The enamel begins to calcify at several points, the central incisor 
at three points, the bicuspids and molars at the tips of the cusps. As 
the calcific matter is deposited the different lobes of enamel should 
join between the cusps, but this does not always happen, and as a con- 
sequence there is left a fissure which is a defect in the continuity of 
lhe surface and must be distinguished from a groove which is only a 
depression and not a defect. In teeth with very high cusps the fissures 
are often quite wide open. In fact they are sometimes so open in 
lower first molars that a fine exploror can be forced between the plates 
at almost any position along the depression between the cusps. It 
is a peculiar thing that often even such a wide fissure will not be the 
seat of caries while others of less width will decay. But the great major- 
ity of all fissures are the seat of caries sooner or later. The conditions 
are the most favorable for development of micro-organisms. Suitable 
material to develop upon is squeezed into these crevices during a meal 
and remains there only to be supplemented at intervals. If it were 
not for the pits and fissures in teeth caries would rarely occur in occlusal 
surfaces, because they would be kept clean by the mastication of food. 
There is no better cleaner of the surfaces of the teeth than the chewing 
of hard tough foods. 

Decay in pits and fissures is so often of a penetrating character that 
great care in examination is necessary. Even though a fine explorer 
will not enter between the plates of enamel there may be a large cavity 
beneath. In fact pulps are often reached by decay and pain be the 
first evidence that anything is wrong without any perceptible break 
in the enamel. In such cases a close observation will reveal a whitened 
area beneath the enamel along the fissure. Any change in the color 
of the enamel usually indicates some defect in the dentin beneath. 
If decay has once begun in a fissure there is only one treatment open 
to the operator. Cut it out in its entirety and include it in the cavity. 
Occasionally fissures may be found in recently erupted molars which 
have not begun to decay and may be prevented from doing so by drying 
them perfectly and squeezing them full of soft cement carried to place 
on the index finger and held there until the cement hardens. This 
treatment will often prevent such fissures from decaying in young 
patients where no other measures are available. 

If every opperator had the opportunity of seeing the micro-organisms 
of decay under a microscope and then seeing the width of the finest 
fissure under the same power there would be no doubt in his mind as 
to what should be done. Fissures are defects and are always a source 
of weakness and especially so when radiating from a cavity. Decay 



1 84 PREPARATION OF CAVITIES FOR FILLINGS. 

having once occurred in a fissure is an indication that it is susceptible, 
and even if the decay be all removed recurrence is almost certain if 
the fissures are nc, cut out to the end and included in the cavity. 
Besides cutting out the fissures it is necessary to cut out angular grooves 
because it is impossible to properly finish a filling flush with the margin 
in these deep V-shaped spaces. If they are left they only form places 
for the lodgment of fruit seeds, etc. 

Technique. — The first step in the preparation of pit cavities such 
as are found on the buccal surfaces of the first molars and the lingual 
surfaces of the upper incisors is to get access to the cavity. Since 
these cavities do not need their outlines increased to prevent further de- 
cay their preparation is quite simple. If the decay has not progressed 
to any extent they may be opened with a drill or a cone bur. Once 
a small bur will enter it is well to cut outwards rather than from with- 
out inwards. A larger and larger bur is used until free access is gained 
to the cavity. Usually there is not much soft decay in the cavity now 
under consideration so the inverted cone bur may be used to complete 
the preparation of the cavity. But if the pit has been the starting 
point of quite a large cavity the enamel can best be cut away with a 
chisel, the softened decay removed with spoon excavators and the 
cavity washed out with a stream of tepid water. If the rubber dam 
be now applied a full view of the cavity is possible and a decision 
as to the location of the outline arrived at. The enamel walls may 
be cut back with a good sized fissure bur, and the remainder of the 
decay removed with spoon excavators and a cement base inserted 
which will become the axial wall of the cavity. As the enamel rods 
around such cavities tend to lean towards the pit no bevel is required 
if the walls of the cavity are cut at right angles to the general plane of 
the enamel surrounding the cavity. 

Occasionally a cavity in the lingual surface of the upper central 
or lateral may have a fissure extending from it quite through the singu- 
lum which complicates its preparation. The fissure usually runs 
clear to the limits of the enamel which in a young patient will be far 
under the gum. Such fissures must be cut out and included in the 
cavity. It may be necessary to pack the gum out of the way with 
gutta-percha. An inverted cone bur will cut out such a fissure more 
rapidly than any other instrument. Size J to J- mm. 

A groove often extends occlusally from a pit cavity in the buccal 
surface of a molar but rarely needs to be extended over the ridge. 
If an occlusal cavity also exists it should be prepared before the buccal 
cavity is filled because when the two cavities are open at the same time 



PREPARATION OF PIT AND FISSURE CAVITIES. 185 

a better judgment can be formed as to whether they should be joined 
or not. 

The order of procedure in preparing fissure and pit cavities in the 
occlusal surfaces of bicuspids and molars is dependent upon the 
extent of the decay. If a shallow cavity has occurred in the central 
fossa of a molar which has fissures radiating from it the edges of un- 
supported enamel may be broken down with a chisel and the outline 
form proceeded with at once. The fissures can be cut out with small 
inverted cone burs or those made into drills as described in a previous 
section. Once a small channel has been cut through a fissure the 
edges may be then broken down with a sharp chisel until the general 
outline has been obtained. An inverted cone bur or a sharp flat-ended 
fissure bur will cut out a flat seat and give the walls the proper form. 
If the cavity walls do not come close to the cusps the enamel wall needs 
no bevel. All that is necessary is to cut the walls at right angles to 
the pulpal wall. If there is now any decay left it may be removed 
with spoon excavators. If the pulpal wall has been cut with an inverted 
cone bur it will not be necessary to cut convenience angles nor will it 
bs necessary to provide for any further retention than that cut with the 
inverted cone bur in forming the seat and walls. Clear the cavity of 
cuttings and it is ready to fill. 

If a deep cavity has occurred, however, the operator is concerned with 
the possibility of the involvement of the pulp and the sensitiveness 
of the tissues from both decay and exposure to changes of temperature. 
It is necessary to determine the condition of the pulp as soon as possible 
because if it must be devitalized it should be done before there is 
any cutting of sensitive dentin in gaining the outline form. Cut 
away the unsupported enamel with a chisel, putting the guard finger 
on the tooth to be cut. Then remove the softened tissue with large 
spoon excavators, having a care for pressure. The spoon may be worked 
under the leathery decay at the edges and flake after flake removed 
without pain. Then wash out with tepid water. As soon as it is 
determined that the pulp is not to be devitalized there are two methods 
open, one is to now flood the remaining decay in the cavity with an 
anodyne which will prevent any pain from exposure and proceed with the 
outline form. Then remove the remaining decay and cover the pulpal 
wall with cement. In this method the deep sensitive tissues are not ex- 
posed for any length of time. The other method is to immediately 
deal with the deep parts of the cavity covering with cement and as soon 
as this hardens proceed with the outline form. By the latter method 
the sensitive tissues are dealt with early in the operation and are pro- 



1 86 



PREPARATION OF CAVITIES FOR FILLINGS. 



tected from thermal changes and the seat for the filling may be cut in 
the cement while the fissures are being drilled out. There is always 
a chance of finding some decay under the edge of the cement when the 
fissures are cut out. The final step in either method is to bevel the 
enamel walls which may be done with a round bur run rapidly or a 
fissure bur in the right angle held perpendicular to the pulpal wall and 
then in such locations as come close to the cusps the instrument should 
be held so as to give the wall a slight bevel. 

A cavity in either of the occlusal pits of the upper bicuspids should 
when completed include both pits and the connecting fissure or groove. 
It is very rare indeed that the tissue between these pits should be left 
if either have failed. It is not necessary to cut this fissure or groove 
more than one to one and a half mm. in width (Fig. 149). Cavities 
in the occlusal surface of the lower bicuspids need not be treated in the 
same way. In the majority of cases there is neither a fissure nor a 
groove joining the pits but a ridge of sound enamel, which should be 




Fig. 149. 





Fig. 150. 



Fig. 1=;: 





Fig. 153. 



rarely cut across because defects have occurred in either or both pits, 
unless, of course, the enamel has been undermined by caries. (Fig. 1 50.) 
There is a crescentic form of the lower second bicuspid which if de- 
fective at all should be cut out in its entirety. (Fig. 151). 

Occlusal cavities in the pits and fissures of the upper molars depend 
in their outline form entirely upon the extent and direction of the fissures 
and angular grooves. A cavity in the central fossa of the upper first or 
second molar is usually simple in preparation. There is often a ques- 
tion, however, as to how far to cut out grooves extending to the mesial 
or to the buccal. The general rule applies, cut all fissures and grooves 
until a good finishing margin can be obtained. Often it is advisable 
to cut the buccal groove out until the break is reached to form the buccal 
surface. In such cases the extremity of the groove should be sloped 
into the center of the cavity giving a decided bevel to the wall. Thus 
a good finishing margin is reached without cutting a slot clear through 
to the buccal surface which would tend to weaken the cusps. Where 
there is a defect in both the central fossa and the disto-lingual groove 
it is always advisable to prepare both cavities at the same time when a 



SMOOTH SURFACE CAVITIES. 



187 



decision can be made as to the advisability of cutting across the trans- 
verse ridge. If cut across it should appear as Fig. 152. If there is any 
thickness of dentin under the ridge it should not be cut across. (Fig. 
153.) There is often a supplemental cusp in the upper first molar 
which has grooves and fissures about it which must be cut out. These 
are often so penetrating that cusps are undermined and must be cut 
away thus facing almost the whole occlusal surface with the filling. 
(Fig. 154.) 

Third molars are irregular in their markings but usually have three 
cusps, two buccal and one lingual, with a pit between and fissures run- 







Fig. 154. 



Fig. 155. 



Fig. 156. 



Fig. 157. 



ning buccally, mesio-lingually and disto-lingually. Neither fissures 
nor grooves pass over the marginal ridges. (Fig. 155.) 

Lower first molars have a central depression which is often defective 
and fissures and grooves extending buccally, lingually, mesially, and 
distally. These cavities are the most uniform of any under this head- 
ing. (Fig. 156.) 

The lower third molars often have the same outline as the lower 
first, while the second will have the appearance of Fig. 157. 

SMOOTH SURFACE CAVITIES. 

1. Cavities in the gingival third of labial, buccal and lingual 
surfaces. 

General Considerations. — The number of cavities and the extent 
of caries in these locations is a true index to the care of the teeth. Cav- 
ities should not occur in these locations if our present views of the 
cause of caries be correct, that is if the patient takes reasonable 
care of his teeth. There is not a buccal or lingual surface except in 
cases of marked irregularity that cannot be reached with a tooth brush. 
It is safe to say to the patient who has such cavities that he does not 
brush his teeth properly and a lesson should be given to him at once. 
In the majority of these cases the first indication of beginning caries 
is a sensitive spot that the patient accidently finds with his finger nail 
or a tooth pick. The area of the sensitiveness gradually increases 
until the tooth brush is not used even on that side of the mouth for 



[88 PREPARATION OF CAVITIES FOR FILLINGS. 

fear of touching the sensitive spot. A break in the enamel occurs and 
extends both mesiaUy and distally. This line is just at the junction 
of the free margin of the gum with the enamel where there is a slight 
protection from the action of the lips. These white lines of superficial 
decay rarely enter the proximal surfaces in young patients but usually 
do so in those of advanced years where the gums have receded to 
some extent. This decay never begins under the free margin of the 
gums but often extends there by undermining the enamel. In such 
cases the sharp edge of the cavity irritates the gum tissue, causing a 
hypertrophy which makes it appear as if caries had begun under the 
gum. 

The proper treatment of labial, buccal, and lingual caries calls for 
careful consideration, not that fillings are often dislodged but that they 
so often fail at the margins. There is usually an area of defective 
enamel extending from the cavity and unless this is all cut out failure 
is certain and even then the operation has not changed the environ- 
ment. The future of fillings in these locations depends more upon the 
patient than upon the perfection of the operation. If after these loca- 
tions on the teeth have been made comfortable the patient cannot be 
induced to regularly and carefully clean them no kind of operation 
other than the removal of the gingival third of the affected surface and 
covering the gingival margin with healthy gum tissue will last even a 
reasonable time. It is often a serious question how much of the enamel 
about such defects should be cut out and included in the cavity. The 
indication of the beginning of caries is a sensitive area. In such cases 
a thorough polishing with powdered pumice followed by chalk, with 
instructions to the patient to follow a simular treatment will often 
prevent the formation of a cavity. Since the general introduction of 
porcelain as a filling material labial cavities may be more freely cut 
for the prevention of future caries. 

Though many labial, buccal and lingual cavities are difficult to 
manage there are a few where decay is slow and the tissue so non-sen- 
sitive that they are among the simplest operations that come under the 
dentist's care. 

Technique. — The form to be given these cavities is simple but 
the management of the operation is exceptionally difficult, be- 
cause of the hypersensitiveness of the dentin and even the enamel, 
and because of the difficulty of getting free access to the cavity. The 
gum tissue has usually grown into the cavity and is exceptionally sen- 
sitive as all pathological gum tissue is. And perhaps the greatest 
handicap of all is, the patient dreads the operation more than all others 



SMOOTH SURFACE CAVITIES. 1 89 

and the operator dreads it himself. Operations in these locations 
have a peculiar tendency to increase the flow of saliva which adds 
materially to the difficulty of the operation and to the discomfort of the 
patient. There are few operations in dentistry where the pain and 
discomfort to the patient are so out of control of the operator as a 
shallow sensitive cavity in the buccal surface of a lower molar in a 
nervous woman. The saliva flows freely, the ordinary therapeutic 
remedies cannot be used unless the rubber is applied and this cannot 
be done without a clamp which will certainly touch the sensitive area. 
Difficulties such as these can only be overcome by an experienced mas- 
ter hand. The hypodermic injection of novocain and adrenalin 
chloride into the gum opposite the end of the root promises results, 
while the injection of cocaine into the tooth with the high pressure 
syring is more to be depended upon. 

In the majority of small cavities even if the gum tissue has grown 
into them it is less painful and more expeditious not to make any at- 
tempt to remove the gum from the cavity until the operation can 
be made, while in large and deep cavities where cotton and gutta- 
percha can be packed and retained without the removal of much of the 
decay it is wise to do so at a previous sitting. When the gum is re- 
moved from these deep cavities one of the difficulties has been over- 
come. In labial cavities the first step after using a solution of cocaine 
on the gum around the neck of the tooth is to apply the rubber dam. 
Dry the cavity. Break down the enamel around the cavity avoiding the 
decalcified dentin. Carefully plan the next step which will be the most 
important in the preparation of all such cavities. It is just as painful 
to remove one layer of the decalcified tissue as it is to remove the whole 
mass. If the cavity be small and no danger of pressing upon the pulp, 
select a location at the mesial or distal wall and sink a sharp hatchet 
or Darby-Perry spoon No. 9 or 10 down to the bottom of the decay 
and scoop the whole mass out at once. Just as this cut is undertaken 
the operator should warn his patient and at the same time divert his 
attention by remarks on some interesting topic. An application of 
hot phenol or phenol and alcohol will relieve the pain incident to the 
exposure of the dentin to the air. The further preparation of the cav- 
ity will not be more sensitive than any other unless it should reach the 
junction of the proximal surface with the labial about one mm. from 
the gum. An inverted cone bur in the direct hand-piece will cut a flat 
axial wall, and extend the other walls in any direction leaving sufficient 
undercut to start and retain the filling. Since the introduction of por : 
celain it is not necessary to discuss the peculiar forms of these cavities 





H)0 PREPARATION OF CAVITIES FOR FILLINGS. 

which make gold fillings the least conspicuous. The outline should 
extend under the free margin of the gum and when finished be covered 
with it. There should be such extension mesially and distally as will 
ensure sound, hard enamel. If any special convenience is required to 
start a gold rilling it should be cut in that part of the cavity furthest 
from the operator and in the greatest thickness of dentin. Any un- 
dercuts in the dentin for retentive purposes should be in opposite walls 
of the cavity. The cavo-surf ace angle may be trimmed with a chisel or 
a round bur or a cone bur. The remaining decay over the axial wall, 
if any, should be removed and the cavity, is prepared for rilling. 
(Figs. 158 and 159.) 

Buccal cavities in bicuspids are treated in like manners but those 
in molars are modified by the difficulty of acces and the impossibility 
of applying the rubber dam when the gingival 
wall is far below the gum. The decay may be 
removed in the same way and the final forming 
of the cavity done with a bur in the right angle. 
There is one frequently occuring buccal cavity 
Fig. ikS Fig. 159. which nearly always fails wdien filled. It occurs 
in the distal third of the buccal surfaces of third 
molars. These surfaces are rarely cleaned by either food or the tooth 
brush. Sooner or later they involve the whole disto-buccal surface 
and the occlusal. While they are small cavities in the buccal surface 
they are so sensitive and difficult of access that proper extension cannot 
be made, hence recurrence of caries is inevitable. As soon as the 
occlusal surface is involved a good dovetail can be cut and the filling 
when inserted sloped off in such a manner as to prevent heavy occlu- 
sion upon it. 

Lingual cavities in the gingival third are rare. They only occur 
because of a marked recession of the gums, or from wearing an artificial 
denture. The preparation of the cavity is similar to that in the labial 
and buccal surfaces. Any variation will depend upon the extent and 
location of the caries. 

2. The preparation of cavities in proximal surfaces of incisors 
and cuspids which do not involve the incisal angle. 

General Considerations. — Patients who have neglected their 
teeth for years take an anxious interest in them as soon as cavities 
appear in their incisors and cuspids. They recognize at once that 
if these teeth become unsightly they have lost one mark of beauty. 
They often allow molars and bicuspids to decay beyond any hope of 
being restored to usefulness under the foolish notion that they can re- 



SMOOTH SURFACE CAVITIES. 191 

tain the anterior teeth even if the others are lost. There is no more 
fallacious notion than this met with in the practice of dentistry, except 
perhaps mistaking the first permanent molar for a deciduous tooth. 
It is difficult to decide what is best to do for a patient of say twenty- 
eight years of age who has lost the power of mastication on his molars 
and bicuspids and has several proximal cavities in the incisors. The 
incisors are used for a purpose for which they were never intended, 
and as a consequence wear down rapidly, cutting off the incisal reten- 
tion to proximal fillings. While it is true that a patient is justified in 
becoming anxious when his anterior teeth begin to decay he should in 
fact be more anxious when his molars and bicuspids show signs of 
being lost, because the anterior teeth cannot be preserved permanently 
if they are used for the mastication of food. Artificial dentures of 
molars and bicuspids alone are but a poor substitute for the natural 
teeth of mastication. The incisors will be used in preference, to their 
destruction. It is the dentist's duty when he sees small proximal 
cavities in the anterior teeth to look into the future sufficiently to edu- 
cate his patient along the lines of being exceedingly anxious about the 
condition of the molars and bicuspids. Fillings in the anterior teeth 
even if small are doomed if they are called upon to bear the stress of 
mastication. These teeth are thin and small and give but a poor oppor- 
tunity for the firm anchorage of fillings and if called upon to do a duty 
they were not intended for there is certain to be failure. This is the 
cause of a large class of failures in fillings in the anterior teeth which 
cannot be classed among failures from recurrence of caries. 

It .has been found by those of largest experience in filling teeth that 
there are certain areas of the teeth more susceptible to caries than 
others. These susceptible areas are found to be those which are not 
habitually cleaned by excursions of food in mastication, or by the friction 
of the cheeks, lips, or tongue. Proximal surfaces of the anterior teeth 
which are close together are not habitually clean, and decay in propor- 
tion to their uncleanness. It has also been observed that not all points 
of proximal surfaces are equally susceptible. All that portion from the 
incisal edge to the contact point is usually immune and in fact the 
actual contact point is rarely the seat of beginning caries but a point 
immediately gingival to the contact is the susceptible area. This is 
as it were an eddy behind the contact where secretions may rest and 
plaques form without disturbance. Each case presents its own little 
variations and should be considered before any operating is proceeded 
with, because in these days of esthetics the whole susceptible area may 
sometimes be removed and restored with gold without exposing the filling. 



I92 PREPARATION OF CAVITIES FOR . FILLINGS. 

It has been noticed for a long time that proximal gold fillings fail 
at the gingival margin, which is true, but closer observation has shown 
that failure rarely occurs in the center of the proximal surface but at 
the linguo-gingival angle and the labio-gingival angle. That portion 
of the gingival margin in the center is usually covered with gum tissue 
and hence does not decay, while both to the lingual and to the labial of 
this point the free margin of the gum crosses the margin of the filling 
and at these points recurrence happens. If the margin is placed im- 
mediately gingival to the contact it is in a susceptible area and failure 
is imminent. Teeth w T hich are spaced in the occlusal or incisal third 
will have their proximal surfaces cleaned by the excursions of food down 
to the contact and if the margin of the filling is incisal to the contact re- 
currence is unlikely. 

The lingual margin is often a location of failure of proximal gold 
fillings in the anterior teeth. Operators have too frequently left the 
lingual enamel plate for the convenience of packing the gold. Cavities 
are often cut quite over on the labial surface for convenience of access. 
Such preparations are a mark of the man who is compelled to do too 
many fillings a day to make a competence. There is often a marked 
concavity both inciso-gingivally and mesio-distally on the lingual sur- 
face of an incisor which leaves the lingual wall little more than enamel 
if a proximal cavity occurs. If such a lingual plate of enamel is left it 
is not strong enough to bear the stress of packing gold against it without 
fracture. Even if this enamel plate does not actually break out during 
the insertion of the gold it becomes checked sufficiently to allow leakage. 
There is only one safe rule to follow. Cut the enamel away on the 
lingual, until what remains is supported by dentin. 

The preparation of small proximal cavities in the anterior teeth 
naturally divides itself into two general classes. Those which are pre- 
pared with a view to the permanency of the filling and those which are 
prepared knowing that the filling will be more or less temporary. If 
all the work of the dentist could be made mechanically correct and its 
permanency was not dependent upon conditions outside of his control, 
dentistry would be practised as a trade and would not have the power 
to retain so many bright minds within its ranks. The varying circum- 
stances that influence the permanency of dental operations make dentis- 
try interesting. The only man who can say that his operations will be 
permanent is the one who does not know or the one w T ho intentionally 
wishes to deceive. The claim of absolute permanency of dental opera- 
tions has done much to discredit the profession because the patient 
who has lost several so-called permanent fillings must think that the 



SMOOTH SURFACE CAVITIES. 1 93 

dentist was ignorant or dishonest, either of which is not creditable to 
the profession. Therefore when we speak of preparations for so-called 
permanent fillings we mean only relatively permanent. 

Porcelain fillings have within the past few years taken such a hold 
on the profession that few gold fillings are now inserted in exposed sur- 
faces of the anterior teeth for patients who value their personal ap- 
pearance. Though this may be true there is still a large field left for 
gold and other fillings. 

The preparation of cavities for those fillings which may be looked 
upon as more or less permanent demands a study of the general con- 
dition of the patient, the oral secretions, the mucous membranes and 
the teeth. There must be a careful study of the susceptible and im- 
mune areas of the teeth. These considerations will usually demand 
the extending of the gingival wall of proximal cavities under the free 
margin of the gum and the labial and lingual walls to those areas 
which are immune to caries, while the incisal margin will be carried 
far enough to the incisal to prevent it from coming in contact with the 
adjoining tooth. If a cavity is so extended there will be no portion of 
its margin in susceptible areas. The gingival margin will be covered by 
healthy gum tissue, the labial margin will always be kept clean by 
foods, the lips, and the brush, the lingual margin by food and the 
tongue, and the incisal margin by food. The only other requisites for 
a fairly permanent filling will be perfect mechanical adaptation to the 
cavity walls and not so much stress of occlusion as will wear, stretch, or 
dislodge the filling. 

The preparation of cavities in proximal surfaces of incisors which 
must of necessity be looked upon as temporary demand less general 
consideration but more consideration of the particular reasons for 
such temporary operations. There must be a perfect understanding 
between patient and operator when operations are to be made which are 
not ideal. The ideal operation may be pointed out to the patient and 
the reasons given for deviations from it. In this way the patient 
understands what is to be expected from such operations and is not 
deceived. And besides if the operator shows himself to be a good prog- 
nosticator his standing is enhanced in the patient's mind and not di- 
minished if the operation lasts no longer than he said. 

While we must admit that all cavities cannot be prepared according 
to an ideal formula there is no intention in this chapter to countenance 
slip-shod operating. Every reason that may be given here for not pre- 
paring cavities according to the outline in a previous paragraph can 
be made an excuse for careless operating. One operator may be so 
13 



104 PREPARATION OF CAVITIES FOR FILLINGS. 

much more skillful and cleft about his work, that what would be too 
painful for another operator's patient to bear would be easily borne by 
his. The rough, unskillful operator will rarely find patients who can 
bear to have proper preparations made in teeth with living pulps, 
while the skillful operator will rarely find cases where perfect prepara- 
tions cannot be made. 

If the proper preparation of a cavity would prove too painful for a 
young patient a temporary operation is indicated, and in such a case 
where cement is to be used, it is not desirable to break down any more 
of the enamel than will ensure sufficient access to remove the decay. 
Then again if small proximal cavities develop slowly and the ex- 
posure of gold would be objectionable it would be manifestly better to 
gain sufficient space to insert small gold fillings than make the ideal 
extensions. Such small fillings are not likely to prevent further decay 
for more than three or four years but the patient has not had gold fillings 
exposed in the teeth for that much of her life. While it is sometimes 
desirable to make cavities that do not have their margins in immune 
areas there are certain cases which are so markedly susceptible to 
caries that they must have their margins carried full well on to immune 
areas. 

Technique. — Separation is a necessity for the proper preparation 
and filling of proximal cavities in the incisors and cuspids. Space 
should be gained in such a way as to prevent the teeth from being sore 
when worked upon. There is no necessity for having the peridental 
membrane so sensitive that the patient experiences pain from every 
touch of the tooth. If slight soreness should occur it is well to support 
the teeth while operating. 

Usually the first step in the preparation of proximal cavities in 
incisors is to chip away the thin enamel with a chisel or a hatchet or 
hoe excavator. These latter instruments are narrow in the blade 
and unless carefully used the points may drop into the sensitive por- 
tions of the cavity. The thin edges of the cavity may be shaved down 
from the incisal to the gingival on the labial and the lingual with the 
corner of a triangular chisel, holding the second finger on the tooth as a 
guard. The blade of the chisel should be carried toward the center of 
the tooth as the edge is carried toward the gingival. A sharp spoon 
will remove the major portion of the decay. At this time a decision 
can be made as to the extent of the carious tissue and the probable 
outline form. 

The outline form having been decided upon, the chisel with a 
keen edge will do more than any other instrument. The enamel may 






SMOOTH SURFACE CAVITIES. 195 

be cut away chip by chip until the incisal margin reaches a point which 
will be kept clean by excursions of food. Both the labial and the lin- 
gual walls may be cut back with the chisel, using the pen grasp, but 
occasionally the thumb and palm grasp will reach the lingual walls 
to best advantage. In opening up the cavity the loose decay was re- 
moved, also the thin enamel edges, so now the chief concern is with the 
proper formation of the cavity for the reception of the filling and the p re- 
vention of future decay without regard to existing caries. Cavities 
of less than 1.5 mm. in diameter without much undermining of the 
enamel can be extended to advantage with a round bur. The largest 
round bur which will enter the cavity is not so likely to cut into the dentin 
and cause pain. The blades may be carried against the enamel cut- 
ting from the dentin outwards. It will be found necessary to extend 
the gingival wall considerably rootwards in many cases to insure the 
margin of the cavity being covered with healthy gum tissue. In the 
case of the small cavity just mentioned a round bur directed against this 
wall in the manner described will work quite efficiently. But in the 
majority of cases an inverted cone bur J mm. in diameter for laterals 
and small cavities, and 1 mm. in diameter for centrals directed 
against the gingival wall and swept across from labial to lingual and 
from lingual to labial holding the hand-piece at such an angle as will 
give the corner of the bur a grip of the tissue will usually cut the dentin 
gingivally and at the same time make a flat seat for the filling with 
convenience angles for starting the gold both at the linguo-gingivo-axial 
angle and the labio-gingivo-axial angle. As the bur cuts into the angles 
the hand-piece should be swayed in an opposite direction and the bur 
carried upward along the labio-axial line angle and linguo-axial line 
angle, thus making a slight groove which should under no cir- 
cumstances extend more than one-third or one-quarter of the distance 
to the incisal retention. In this connection it must not be under- 
stood that grooves are recommended in either the labial or lingual walls. 
A slight extension incisally from the convenience angles for holding the 
filling more securely during its insertion is all that is desirable. As 
the gingival wall is thus formed the enamel edge will not be cut away 
which can be done with a narrow chisel introduced from the labial. 
Such a chisel should have a fine neck so it may be held at any angle. 
A round bur may be used to trim the enamel at the gingival but must 
be held firmly, allowing it to rotate in the proper direction, or it may 
catch on the edge and pull the rubber off or cut a deep notch in the 
margin. The outline at the junction of the lingual wall with the 
gingival and the labial with the gingival must be cut with great care 



100 PREPARATION OF CAVITIES FOR FILLINGS. 

otherwise too much bevel will occur, or these points will not be ex- 
tended far enough to ensure a clearing margin. It must be kept in 
mind that these are vulnerable points in these fillings. 

Any decay or decalcified tissue that might be remaining in the 
cavity should be removed. Spoon excavators with thin cutting blades 
and of a size to readily enter the cavity will rapidly remove the remain- 
ing defective tissue. Darby-Perry No. 9, 10, 2 and 4 are thin bladed 
spoons suitable for small cavities. 

Give the cavity proper form to resist any stress that may come 
upon the filling, also make it of such a form that it will be convenient to 
fill. In cases where the gingival wall does not need extension for pre- 
vention, and the outline form has been obtained and the decay re- 
moved, the resistance form, the retentive form and the convenience 
form may be all made at the same time. An inverted cone bur \ mm. in 
diameter for small cavities and J or 1 mm. in diameter for larger cav- 
ities in centrals and cuspids will cut a flat seat at the gingival by holding 
the instrument parallel with the long axis of the tooth and carrying it 
well into the linguo-gingivo-axial angle and into the labio-gingivo- 
axial angle as before mentioned. In these cavities it is impossible to 
cut the gingival wall at right angles to the long axis of the tooth with 
an inverted cone bur because the shaft cannot be held exactly parallel 
with the long axis, but if the dentin be cut slightly deeper at the gingivo- 
axial line angle the outer border or enamel wall may then be trimmed 
sloping inward except at the cavo-surface angle which should be 
beveled. The main feature of the gingival wall is to be flat from labial 
to lingual and form a right angle or an acute angle with the axial wall. 
There should be no deep grooving of the gingival wall nor cutting of 
deep pits. A flat seat with walls forming right angles from it is the best 
form to resist stress. The necessary retentive form in these cavities is 
provided for in the cut into the linguo-gingivo-axial angle and the labio- 
gingivo-axial angle and a slight cut into the dentin at the junction of the 
lingual wall with the labial at the incisal extremity of the cavity. At 
these points the dentin is the thickest and the cuts are directed away 
from the pulp. The incisal retention can be completed with an acute 
angled hatchet, S. S. W., No. 27. This instrument may start to cut at the 
labio-axial line angle about a millimeter from the incisal retention and 
be carried toward the incisal and then started again in a similar position 
on the lingual carrying each cut around the incisal retention started 
with the bur. This action of the instrument will deepen the cavity 
rapidly. It is not necessary to make a deep undercut at this point, it is 
more important to have a good bulk of gold even at right angles to the 



SMOOTH SURFACE CAVITIES. 



197 



axial wall than a line hole bored deeply. The lingual wall should 
not under any circumstances be grooved in its length nor should 
the labial. There are cases where a short groove may be extended 
from the convenience angles but even these are not necessary in small 
cavities. 

A source of weakness in fillings at the incisal margin is the thinness 
of the gold. The enamel rods on distal surfaces have a decided incline 
towards the incisal, and if beveled at all makes the gold thin. This 
difficulty may be overcome if the incisal retention is some distance 
gingival to the cavo-surface angle by making a slight concavity from 
the incisal retention to the cavo-surface angle with a round bur. This 
deepening between the labial and lingual cavo-surface angles will 







Fig. 160. 



Fig. 161. 



Fig. 162. 



Fig. 163. 



thicken the gold to the very edge. Such a concavity cannot be cut 
deep or the retention might be destroyed and the enamel plates under- 
mined. (Figs. 160, 161, 162, 163.) 

The enamel wall may be trimmed and beveled with the chisel, 
round bur or strip, and where there is abundance of space the disk. 
The disk and strip are very treacherous instruments but in the hands 
of those who are willing to study their peculairities are the most tract- 
able at our command. A strip narrower than the inciso-gingival di- 
ameter of the cavity held tight and carried back and forth without 
pressure against the walls will finish an enamel wall in these cavities 
as no other instrument can. A disk in large cavities may be satis- 
factory but it should not be permitted to reach the junction of the 
gingival wall with the labial or lingual or too much bevel will be the 
result. A round bur is better adapted for these positions. 

If the cuttings are now removed from the cavity and the tissue over 
the pulp carefully inspected the filling may be inserted. 

Lower incisors and cuspid cavities demand special treatment 
insofar as these teeth differ in form from the uppers. They have 
smaller and longer crowns than the uppers. They are much narrower 
mesio-distally and the contact points are always at the incisal edges. 
The latter fact together with concave proximal surfaces at the gum 
line make operations prone to failure. The teeth are so thin that the 



ioS 



PREPARATION OF CAVITIES FOR FILLINGS. 



labial and lingual plates of enamel have but little dentin between them, 
and if retention be cut deeply between these plates for the incisal reten- 
tion the corner is almost certain to fracture. In some of these teeth 
the pulp extends far into the crown and is a source of difficulty. 
Cavities which do not extend close to the incisal edge are simple in prep- 
aration and the fillings of fair permanency. There is little or no stress 
on small fillings in the lower anterior teeth. Retentive form is made 
as in the upper. In fact the preparation is the same except that there 
is not as much space between the teeth, and all the instruments should 
be smaller. Retentive form and convenience angles may be cut with 
a h mm. inverted cone bur holding the shaft at right angles to the 
long axis of the tooth. The base of the bur may be carried down the 
lingual wall and sunk into the gingival at the linguo-gingivo-axial angle. 
The labio-gingivo-axial angle may be cut in like manner using a bur in 
the right angle hand-piece. The incisal retention may be cut as in the 
uppers. 

3. Preparation of proximal cavities in incisors and cuspids which 
involve the incisal angle. 

General Considerations. — Proximal cavities in incisors and cuspids 
which have become so extensive as to involve the incisal angle have 
usually been filled before. The conditions which caused the failure 
of the former filling will be of value in determining what form of 
preparation is desirable for the new cavity. In such cases as have 
not been filled before there is often difficulty in deciding whether the 
incisal angle should be cut away or not. Corners of enamel often 
stand the force brought upon them before the filling is inserted and 
break off shortly afterwards. There may be two reasons for this, 
a tooth with a cavity in it is usually saved a little in mastication but 
as soon as made comfortable by a filling it receives full force upon it. 
Or the corner of enamel may be checked during the insertion of the 
gold and come away later. It is a safe practice to remove a corner 
of enamel when it has not a support of dentin if the cavity is to be 
filled with gold. As patients become older the enamel is more and 
more worn away and seems to check and split more readily than 
thicker tissue. This is especially true where proximal fillings have 
failed from wearing away of the tooth tissue leaving the filling to carry 
too much stress. The margins of cavities in such teeth demand free 
cutting away of tissue and careful operating to prevent checking of 
the edges. 

The character of the articulation, the peculiar motion of the teeth 
on each other in mastication and the force of the occlusion all influence 









SMOOTH SURFACE CAVITIES. 1 99 

the operator in deciding the form of preparation. In most of these 
extensive operations failure does not occur from primary decay about 
the margins, but is secondary to the shifting of the filling or checks 
in the enamel. If a patient should have no molars and bicuspids 
suitable for mastication large fillings in the incisors need to be much 
more firmly seated than if there were good posterior teeth for masti- 
cation. Teeth which come together with a kind of anterio-posterior 
motion, sliding the lowers from the labio-incisal angle of the uppers to 
the gingival will drive almost any filling from the upper teeth. And 
if the lower teeth happen to require fillings, they will be as likely to 
fail as the uppers. 

Outline Form. — The determination of the outline form in proxi- 
mal cavities which involve the incisal angle is not one of extension for 
prevention in the ordinary acceptation of the practice. It is extension 
to more securely anchor the filling rather than to prevent decay. 
The proximal surfaces are usually so far extended before such an 
operation is contemplated that no further extension is necessary to 
prevent recurrence of caries on these surfaces. The outline form 
depends on the age of the patient, the extent of the caries, the thickness 
of the tooth, the amount of wear on the incisal edge, the friability of 
the enamel and the character of the occlusion. Depending upon these 
conditions there are five methods of preparation open to the operator. 
The first to consider is a modification of the method used in preparing 
proximal cavities which do not involve the incisal angle. The indi- 
cations for this form of preparation are thin teeth, young patients, 
not very heavy occlusion, not much of the incisal edge involved and 
not much undermining of the corner. 

Resistance Form. — The seat and labial and lingual walls are 
prepared as already described, except that the seat is made broader 
and longer and the grooves are made deeper. The filling will be 
called upon to bear heavier stress than those described in the former 
section and requires a greater seat. The labial and lingual margins 
should be a straight line from the incisal to the point where they curve 
to form the gingival wall. 

Retentive Form. — Much care is necessary to avoid cutting out 
all the dentin between the labial and the lingual enamel plates in 
cutting the incisal retention. To be of the most value this retention 
must be as near the point of stress as possible and large enough to 
contain a sufficient bulk of gold to have strength to resist the forces 
of dislodgment. The horn of the pulp is not always secure from an 
accident in cutting this retention. It is generally sufficient to make the 



200 PREPARATION OF CAVITIES FOR FILLINGS. 

occlusal wall of this retention at right angles to the long axis of the 
tooth, but to be certain of doing this it is well to aim to make the 
depth of the retention closer to the incisal than that at the axial wall. 
Technique. — With a wide chisel cut away the corner, shaving 
both the labial and lingual to the gingival. Some patients' only fear 
is the slipping of the instrument and wounding the gum or touching 
the sensitive portions of the cavity. In such cases a coarse disk or a 
thin stone will trim away the enamel corner readily and with less 
anxiety to the patient. Remove the softened dentin and form the 
seat with an inverted cone bur i mm. in diameter which may be held 
parallel with the long axis of the tooth and carried into the labio- 
and linguo-gingivo-axial angles, cutting deeply into the dentin at these 
points and carrying a groove towards the incisal less than half way. 
The incisal retention may be cut with an inverted cone bur held at right 
angles to the axial wall giving the corner of the bur a catch into the dentin 

some distance gingivally to the final occlusal 
wall. Slight grooves may now be cut toward 
the gingival from the incisal retention. A disk 
is the only instrument to finish the enamel walls. 
It can be held to cut the enamel parallel with 
^_ , r, the length of the rods and then to slightlv bevel 

J*IG. 164. FlG. 165. ° # ° 

the outer third. The incisal cavo-surface angle 
will bear considerable bevel. Remove any remaining decay from the 
axial wall and clean up the cavity walls. (See Figs. 164 and 165.) 

The second method is suitable in thin teeth, young patients, incisal 
surface not much worn nor not much involved, corner undermined. 
Chiefly useful in laterals. Pits and grooves in the lingual surface may 
be included in such a preparation. 

The outline form is the same as in the last case except that there 
is a tongue or dovetail cut in the lingual surface at least one and a 
half mm. from the incisal edge depending upon the form of this sur- 
face. The margins of the dovetail should join with the lingual wall in 
rounded corners. 

The resistance form at the gingival is the same as in the last case. 

The retentive form in the incisal region is entirely different. 
Instead of cutting between the labial and lingual plates as in the former 
case the incisal retention is cut into the lingual surface in the form of 
a dovetail. The dovetail is cut about one and a half mm. in depth, 
depending upon the thickness of the tooth and the nearness of the 
pulp. The direction depends upon whether there are defects in the 
enamel of the lingual surface or not. It is generally advisable to 








SMOOTH SURFACE CAVITIES. 201 

make this retention at right angles to the proximal wall and about 
one and a half mm. inciso-gingivally and about one and a half to two 
mm. mesio-distally. To be of the greatest value as retention it 
must be cut as near as possible to the incisal but must not be so near 
as to weaken the edge. 

Technique. — The technique up to cutting the supplementary 
retention in the lingual has already been described. It is always 
difficult to control the hand-piece to cut into the lingual surface of any 
tooth and it is especially difficult to do so in this case, if it becomes 
necessary to use the right angle. Where this form of preparation is 
advisable the lingual surface is usually markedly concave inciso-gingi- 
vally thus making it almost impossible to reach it with the straight 
hand-piece. Unless the operator has confidence in his ability to hold 
the hand-piece and operate through the mouth mirror it is better to 
raise the enair, tip the patient's head back and operate by direct view. 
A No. h or | mm. inverted cone bur should be held at right angles 
to the lingual surface of the tooth, starting the corner of the bur on the 
lingual wall of the cavity at the junction of the enamel with the dentin. 
This bur will cut a slot the full depth of the enamel and the necessary 
distance towards the opposite side of the tooth. The enamel edges 
should be cut back and, if need be, the slot cut larger and made reten- 
tive in form, that is, the incisal and gingival walls must be slightly 
undercut. (Figs. 166, 167 and 168.) 






Fig. 166. Fig. 167. Fig. 



The third method of preparation is indicated in thin teeth, corner 
undermined, edge much involved, lingual plate of enamel badly de- 
cayed, and heavy occlusion and appearance of gold not a serious 
objection. In such cases there is a step cut in the incisal surface, its 
width depending upon the extent of the destruction of the cutting 
edge. As a rule the step should extend mesio-distally farther than the 
width of the filling to be supported. The depth depends upon the 
weight of occlusion and the thickness of the tooth. 

Technique. — When it has been decided to cut across the incisal 
exposing the gold on the labial surface a stone is the most suitable 
instrument to begin with. Cut the incisal edge down the width and 



202 



PREPARATION OF CAVITIES FOR FILLINGS. 



depth required. Prepare the proximal cavity as in case two. With 
an inverted cone bur cut a groove from the proximal cavity across the 
step between the labial and lingual enamel plates, deepening and 
enlaging the groove at its extremity. A good deal of care is necessary 
in cutting this groove to keep it from coming too close to the labial 
plate and at the same time have it large enough to contain sufficient 
gold to have strength. 






Fig. 169. Fig. 170. Fig. 171. 

The fourth method is more frequently applicable than either of the 
last two described. This method of preparation was first described 
by Dr. Johnson and takes his name. It is indicated in thick teeth, 
much worn, corner undermined, edge much involved, heavy occlusion, 
brittle enamel, old patients, lingual surface not too much involved. The 
successful preparation of such a cavity and filling it with gold demands 
much consideration before it is undertaken and careful manipulation 
afterwards. 

Technique. — The seat and proximal surface are prepared as 
in the last two cases. Dependence for the retention of the 
filling is in the step cut across the incisal. The step does not 
involve the labial plate and yet the occlusal surface is completely 
covered with gold. The step is largely at the expense of the lingual 
surface. The labial wall must in consequence be cut with a definite 
angle with the axial wall. The labial wall in the step must also meet 
the pulpal wall with a definite angle to give the necessary resistance to a 
heavy occlusion coming against the lingual surface of so large a filling. 

The outline from a labial view is shown in Figure 169. There is 
no exposure of gold except as a proximal filling. If the incisal sur- 
face has been sufficiently worn to expose the dentin the outline will 
show the whole occlusal surface faced with gold. (Fig. 170.) The 
lingual outline will show almost a third of the surface covered with 
gold. (Fig. 171.) Those surfaces of the tooth which are exposed to 
heavy occlusion are covered w T ith gold and those surfaces which are 
exposed to view from without show but little gold. 

An inverted cone bur held against the axial wall at right angles to 
the long axis of the tooth will, if carried across the incisal, cut the step 
about 1 mm. in depth. This first cut must be kept well to the lingual 






SMOOTH SURFACE CAVITIES. 



203 




Fig. 172. 




Fig. 173. 



or the labial plate may be so thin as to expose the gold through the 
enamel. The lingual plate may now be trimmed away with the 
chisel. Usually it is necessary to carry the inverted cone 
bur across the incisal again to make the step flat and at right 
angles to the stress. The extremity should be deepened to 
give additional strength and to resist tipping. The groove 
through the dentin forming the step should not be more than 
\ mm. deeper than the lingual wall except as it approaches 
the extremity where it may be slightly deeper, while at the 
same time the lingual wall is not trimmed away so much at this point. 
There may in some cases be some difficulty in obtaining sufficient resis- 
tance to forces which may happen to be applied to the labial surface. 
But as a rule fillings are rarely tipped to the lingual. 

Finishing the enamel walls demands a careful study of the direction 
of the enamel rods at every point. The labial wall of the 
step may be beveled with a fissure bur, a disk or a round 
bur. This wall is sloped from the junction of the labio- 
incisal angle to the pulpal wall of the step. The extremity 
of the step is best trimmed with a round bur. The lingual 
wall of the step must have a slight bevel and join with 
the proximal lingual wall in a rounded form. A sharp 
corner at this junction would invite failure either during the insertion 
of the filling or afterwards by the occlusion. At the junction of the 
labial wall of the step with the proximal wall is a source of weakness 
if a sharp angle is left to the enamel. A small disk in the right angle 
will reach the lingual cavo-surface angle and also the labial. 
The -fifth method is applicable in those cases where there 
is an edge to edge bite, wearing the teeth down to expose 
the dentin and perhaps loosening the incisal retention in a 
small proximal filling. There is not much of the incisal 
edge lost and yet a proximal filling cannot be retained be- 
cause of the rapid wearing of the tooth and the difficulty 
of cutting an incisal retention. The surest method to follow 
is to cut the step clear across the incisal including all the exposed 
dentin and beveling both the labial and lingual enamel walls toward 
the pulpal wall of the step. Of course, enough of these walls must be 
cut down to face the whole end of the tooth with gold. The prepara- 
tion of the proximal cavity should be done as before described except 
that it does not require any provision for retention because the step 
will provide all the resistance necessary. There is little or no force 
to drive the filling to the labial or the lingual because there is little 




Fig. 174. 




204 PREPARATION OF CAVITIES FOR FILLINGS. 

loss of these surfaces. The chief point of difficulty in preparation is 
at the junction of the proximal cavity with the step. There must be 
bulk enough of gold at this point to ensure against stretching. If a 
sharp corner is left at this junction it tends to leave a point to start 
the stretching of the gold. The technique of preparing this cavity is 
so much like those just described that it is not necessary to repeat it. 
(Figs. 172, 173 and 174.) 

Shoeing. — There is a class of cavities met with in old patients so 
similar to the one described in the previous paragraph that it might 
not be out of place to describe their preparation here. They are 
strictly speaking occlusal cavities but they are not similar in origin 
to other occlusal cavities already described. As patients advance 
in years their teeth become worn until the dentin is reached which soon 
hollows out in a cup shape on the occlusal surface. This exposed 
dentin often becomes quite sensitive to acids and in fact is 
dissolved or worn away so rapidly that the pulp is often 
involved. The teeth become much shortened and unsightly. 
To foresee and prevent such unhappy results is the duty 
of the dentist. If a tooth seems to be cupped out even 
IG ' I75- though there is little direct antagonism of the opposing tooth, 
it is well to prepare a cavity for the reception of a gold filling which 
will cover the exposed dentin and prevent its further wear. The an- 
terior teeth, both upper and lower, are chiefly subjected to such wear- 
ing because so many people have lost their molars and bicuspids. 

Technique. — The technique of preparation is simple. This 
eburnated dentin is not usually sensitive to cut. An inverted cone 
bur can be held parallel with the long axis of the tooth 
and carried across the occlusal surface cutting a groove 
about a millimeter in depth. As the tooth is worn down a 
good deal it is quite thick labio-lingually giving ample room 
for good anchorage. The extremities of the groove should 
not come too close to the mesial or distal surfaces. The FlG ^ 6 
inverted cone will make all the undercuts necessary to keep 
the filling from being lifted from the cavity which is the only force that 
can dislodge it. The walls should be sloped into the cavity and the 
finished filling should come over the entire end of the tooth and be of 
sufficient thickness to resist stretching or curling up at the edges 
from constant hammering of the opposing teeth. (Figs. 175 and 176.) 
PULPLESS INCISORS HAVING LARGE PROXIMAL CAVITIES. 
While the majority of incisors which have lost their pulps and have 
large proximal cavities require to be filled with porcelain or should be cut 




PULPLESS INCISORS HAVING LARGE PROXIMAL CAVITIES. 205 

off and restored by a crown there are cases which should be filled with gold. 
The difficulty in preparing such cavities is to avoid cutting away 
the dentin; because so much has been already lost by getting access 
to remove the pulp there is no strength left to retain and support a 
filling. In thin teeth not much worn on the incisal, a fair amount of 
dentin, and not much filling exposed to occlusion the chief retention 
may be obtained in the pulp chamber. The pulp chamber should be 
filled with cement and then the gingival wall cut wide and flat as if 
the pulp had receded markedly. Grooves may be cut in the labial and 
lingual walls part of the distance to the incisal, depending upon the 
thickness of the tooth. The incisal retention should be cut with an 
inverted cone bur placing it into the pulp chamber and cutting towards 
the incisal, thus getting a good undercut without going near the incisal. 
The aim should be to make up in bulk of gold (the greater portion of 
which will be in the pulp chamber) for not getting the retention as 
near the point of stress as in other cases. 

If the tooth is thin and the decay together with the cut- $y ill 
ting to remove the pulp has involved a good deal of dentin JfM 
any further cutting of dentin is contra-indicated. It is I [ 1 ; 
better to depend for retention of the filling upon a post \jy j 
cemented in the root canal and extending far enough into FlG 
the cavity proper to give a good attachment for the filling. 
There is no further preparation of the cavity required than to give it 
proper outline form and resistance form; the post will provide the 
retention. The technique of inserting a post in an incisor so that a 
gold filling may be condensed around it is not always easy. Select a 
piece of iridio-platinum wire No. 16 for a central or cuspid and No. 
18 for a lateral. Ream out the canal about five to seven mm. in 
depth, not the same diameter the full depth, as it is usually better 
to taper the wire slightly. To do this it is best held in a pin vise for 
filing. With heavy pliers give it the necessary bend to enter the canal 
and project in the center of the cavity so that gold may be 
packed between it and the cavity walls and also cover it at 
the surface. To accomplish this it will be necessary to fit 
the pin in the cavity, mark it about the proper length and 
remove it to cut it off. Then file it down to some extent 
IG ' iy ' and perhaps flatten that portion extending into the cavity 
with a hammer on the anvil so as to conform w r ith the flat shape of 
the tooth labio-lingually. Before setting in cement it should be 
tried in and note taken of its length, its size and proper position 
to allow gold to be packed around it, and its capability of retaining the 
filling. (Figs. 177 and 178.J 




JOO PREPARATION OF CAVITIES FOR FILLINGS. 

4. Preparation oj cavities in bicuspids and molars which do not 
involve the occlusal surface. 

While the general rule is laid down that all proximal cavities in 
bicuspids and molars should be extended through to the occlusal sur- 
face there are cases in which it is better practice not to do so. In the 
very old, the very young and in cases of immunity to caries it is not 
always wise to extend proximal cavities to the occlusal surface, but 
such operations must be looked upon as temporary in character. 

There is more or less recession of the gums around the necks of 
the teeth as age advances. The gum tissue which once filled the inter- 
proximal space does not more than half fill it at fifty or sixty years of 
age. These open spaces between the teeth serve as pockets for the 
collection of food which ferments and acts as a starting point of decay. 
The cementum is exposed and decays rapidly. In such cavities which 
are usually shallow and girdle the tooth it would be manifestly unwise 
to extend through to the occlusal surface. There is plenty of access, 
the contact is far occlusal to the cavity and the tooth is thick enough 
occluso-gingivally to bear any stress which might come upon it. Be- 
sides old patients should be treated with a good deal of consideration. 
Radical and painful operations should be reserved for those in the vigor 
of life. Old people dread dental operations even more than the child 
who has been told of the horrors of the dental chair. 

For many reasons, as has already been said, it may not be wise to 
make a full extension of cavities occurring in the proximal surfaces of 
the teeth of the very young. These patients are often so nervous 
and restless in the dental chair that anything like ideal operating 
cannot be undertaken. It is better in such cases to do temporary 
work rather than create a dread of dental operations in the minds of 
young patients. Again the warning must be sounded that oversen- 
sitiveness, etc., must not be made an excuse for improper extensions. 
While we must all admit that such cases are met in practice yet there 
are not nearly so many of them as some of the old operators would 
have us believe. 

Often a large proximal cavity is found in the mesial surface of a 
first permanent molar and after it has been opened up and prepared 
for filling the beginning of a cavity is found in the distal surface of 
the second bicuspid. Now comes the problem. What should be 
done with such a defect ? If it is left without a filling it is certain to 
decay. If a small filling is inserted whose margins are in contact 
with the adjoining filling recurrence is almost certain within a very few 
years. Should the whole proximal surface together with the neces- 






PULPLESS INCISORS HAVING LARGE PROXIMAL CAVITIES. 207 

sary step be cut out now, or should an attempt be made to get a clear- 
ing margin to a filling confined to the proximal surf ace ? The answer 
to these questions depends upon the conditions present. If the patient 
be a young girl and caries progressive and a full extension would seem 
impossible a small cavity may be prepared. It must be explained to 
the patient that this is a temporary operation which will need careful 
examination every few months. Any change of color about the filling 
will be a signal for its removal. By this method perhaps two or three 
years have been gained and the patient at this time will be glad to 
have a more permanent operation made. If the patient be robust and 
the dentin not too sensitive and a tendency to caries and lack of care 
of teeth, the cavity should be prepared in the most ideal manner. Then 
there is the middle course which may be followed if there is a marked 
immunity to caries. The cavity may be extended as much as possible 
to clear the margins but yet confining it to the proximal surface. 
There are many cases of thick necked teeth where this preparation 
will have fairly good cleansing margins. The management of this 
type of case in practice will indicate w r hat may be done with similar 
cavities in other locations. 

Many times small cavities are found in the proximal surfaces of 
teeth in patients of middle life which have not increased in size for years, 
or perhaps at one time decay was rapid but for some cause or another 
has ceased. The walls of these cavities will be dark or even black in 
color, the enamel about them does not seem to have its normal his- 
tological structure when cut, the dentin in the bottom of the cavity 
does not seem to be sensitive. In some of these cases there may be a 
slowly progressing caries at only one location in the cavity. Radical 
extensions of cavity margins are not indicated in such cases. It is 
not necessary to cut such cavities through to the occlusal surface if 
there is abundance of access and there is sufficient thickness of tissue 
left to bear the forces of occlusion. 

Technique. — The technique of preparing proximal cavities in 
bicuspids and molars which do not involve the occlusal surface is 
quite simple. They are simple cavities and are prepared as buccal, 
labial, or lingual cavities. There is no force to dislodge the filling. 

5. Preparation of cavities in the proximal surfaces of bicuspids and 
molars which involve the occlusal surface. 

The preparation of cavities in the proximal surfaces of molars and 
bicuspids opens up the "question of extension for prevention" again. 
While there may be excuses for not extending proximal cavities in 
the anterior teeth there cannot be the same excuses for not doing so in 



2o8 PREPARATION OF CAVITIES FOR FILLINGS. 

the bicuspids and molars. These teeth are wider bucco-lingually 
than the anterior teeth, the proximal surfaces are often flat which in a 
measure accounts for more frequent failures in these teeth than in the 
anterior teeth. The bicuspids and molars are usually closer together 
and rarely as well cared for as the incisors. 

The outline form depends upon the age, and sex of the patient, 
the character of the carious process, the strength of the closure of the 
jaws and the friability of the enamel. The extent of the caries is a fac- 
tor in deciding the location of the outline only when it has gone beyond 
the susceptible areas. All small cavities of decay are extended until 
immune areas are reached. The gingival wall is cut away until the 
margin of the rilling will be covered by healthy gum tissue. The buc- 
cal and lingual walls are extended until the margins are quite clear 
of the adjoining teeth and may be kept clean by the action of the lips, 
the tongue, the tooth brush and food in passing over them. The 
outline of such cavities on the occlusal surface depends to some extent 
upon the depth and direction of the fissures. While cutting proximal 
cavities through to the occlusal gives more perfect access to the proxi- 
mal cavity it also gives an opportunity for cutting out defective grooves 
or fissures in the occlusal surface and forming a step for the filling 
which is the chief source of retention. The outline in the occlusal 
should be formed so as to give the greatest amount of retention for 
the filling with the least cutting away of tissue. The buccal ana 
lingual walls should be parallel and at right angles to the seat of the 
cavity. There should be no acute angles or irregularities in the outline. 

Technique. — In the ordinary proximal cavities where the occluso- 
proximal marginal ridge has not been broken away and but slight 
defects in the occlusal fossa the simplest method of procedure is to 
cut into the fissure in the occlusal with an enamel drill or fissure bur 
about \ mm. in diameter. This instrument should be carried right 
through the marginal ridge leaving a slot, the edges of which can be 
broken down with a chisel. If the cavity be a distal one, Black's side 
instruments work admirably. At this juncture the decay in the proxi- 
mal cavity may be removed with spoon excavators and the cavity washed 
out with a stream of tepid water. If the rubber is now applied and 
the cavity dried the full degree of extension may be decided upon. In 
the great majority of cases where the proximal decay has been at all 
extensive the buccal and lingual walls may be cut back with the 
chisel. If the enamel is supported by dentin it will be impossible to 
cut it back with the chisel until the dentin is first removed. This may 
be done with an inverted cone bur which is placed in the seat of the 



PULPLESS INCISORS HAVING LARGE PROXIMAL CAVITIES. 209 

cavity and carried from the center to the buccal and then carried towards 
the occlusal undermining the enamel. This may be repeated on the 
lingual wall and if the gingival needs extension it may be cut with the 
same instrument. The chisel will now shave back the enamel slightly 
beyond the point of the removal of the dentin. A narrow necked 
chisel may be passed between the teeth to shave the gingival enamel 
away. In many of these cases it is difficult to control an inverted 
cone bur along the seat and keep it from jumping out of the cavity 
or dropping dangerously near the pulp. If an Ivory matrix is adjusted 
the bur may be held tightly against it while it is cutting and thus pre- 
vented from doing what was not intended. The outline of the step 
should be completed by carrying an inverted cone bur 1 mm. in di- 
ameter as far to the opposite side of the tooth as the fissures extend and 
at this point carried to the buccal and lingual enough to make the cavity 
at the extremity a little more than ^ mm. wider bucco-lingually than 
any other point in the step. Instead of widening the extremity of the 
step as just described it may be deepened about half a millimeter and 
slightly undercutting buccally and lingually. This method is applic- 
able w T here there are no fissures or angular grooves requiring removal. 
There is always some difficulty in properly trimming the enamel at the 
junction of the occlusal outline with the proximal. A careful study 
of the behavior of the enamel as it is cut away is the only guide to the 
proper beveling. 

The resistance form of cavities in bicuspids and molars is 
of first importance because these teeth and their fillings are called 
upon to bear heavy pressure and sudden impacts from hard substances 
in the closure of the jaws. The chief dependence to resist this heavy 
stress must be in a flat seat and step which are at right angles to the 
force applied. There should be no dependence put in grooves or under- 
cuts in the w r alls of the cavity to resist the stress of occlusion. 

As the outline form is being gained the resistance form is being 
provided for. The inverted cone bur which was swept across the 
gingival wall made the seat flat from buccal to lingual and from the 
cavo-surface angle to the axial wall. And as the step was being cut 
out with the same form of instrument it was made flat. The junction 
of the axial wall with the step should be slightly rounded just so as not 
to leave a sharp corner which might be the starting point of stretching 
the gold under the heavy biting in some mouths. If decay has 
removed a good deal of the axial wall thus lessening the area of the 
step it may be restored with cement and formed as if it were dentin. 

The retentive form is largely provided for in the resistance form 
14 



2IO 



PREPARATION OF CAVITIES FOR FILLINGS. 



and the outline form. However, there are forces which may dislodge 
fillings in bicuspids and molars though they would resist the heaviest 
of stress. Such hllings must be so placed as to prevent their being 
tipped from the cavity or lifted directly out. The tipping stress is 
overcome by the dovetail in the occlusal surface and by providing 
sufficient bulk of gold in the step so that portion of the filling in the 
proximal surface may not be broken away from the step. As the 
buccal and lingual walls are being cut back the inverted cone bur is 
allowed to cut deeply into the bucco-gingivo-axial angle and carried 
occlusally about two-thirds the distance to the step, thus making the 
slightest grooves, which widens the cavity bucco-lingually at the 
seat and not at the step. It must not be understood that the outline 
is wider bucco-lingually at the seat than at the step. It is only in the 
depth of the cavity that it is wider. A slight undercut in the step 
will provide against the lifting of the filling if the walls cannot be wid- 
ened as just mentioned or if the proximal cavity is to be filled with non- 
cohesive gold or tin-and-gold, and finished with cohesive gold. 

The convenience form has already been provided for in the 





Fig. 179. Fig. 180. Fig. 181. Fig. 182. Fig. 1S3. Fig. 184. 

angles cut at the seat and in opening up the cavity to the occlusal to 
gain free access. There is no more fatal mistake in the formation 
of this cavity than allowing the proximal walls to diverge as they ap- 
proach the gingival. Even if such cavities are successfully filled the 
least condensation of the filling after it is inserted will result in the 
gold drawing away from the margins. 

The enamel walls should be first cut in the length of the rods and 
then the cavo-surface angle beveled the required amount at every point. 
If the operator notices the manner of cleavage of the enamel while 
trimming the walls he will be guided in their final polishing and 
beveling. Any mistake in the proper bevel of the enamel is sure to 
be followed by fractures of the enamel around the filling. 

Technique.— A disk will trim, bevel and polish part of the buccal 
and lingual walls on the proximal and part on the occlusal. A disk 
will not reach the margins near the gingival without cutting too much 
bevel nor will it reach the walls at the extremity of the step. These 



PULPLESS INCISORS HAVING LARGE PROXIMAL CAVITIES/ 211 

locations must be trimmed with a bur. A chisel will trim the gingival 
wall. Darby-Perry gingival enamel chisels will sometimes do good 
service at these points. (Figs. 179, 180, 181, 182, 183 and 184.) 

If any decalcified tissue remains over the axial or pulpal wall it 
may now be carefully cut away and the cavity cleared of any chips. 

The procedure of preparing these cavities is slightly modified if 
the proximal decay is extensive enough to undermine the enamel 
both buccally and lingually. In such cases the walls are readily cut 
away with the chisel and the seat is easily formed. What is of con- 
siderable moment in these cases is the support of the buccal and lin- 
gual cusps and at the same time to get enough resistance form for the 
filling. Caries has reduced the area of the step and the area of the 
seat cannot be increased by cutting into the tooth until the axial wall 
is at right angles with the seat and step, without involving the pulp. 
The next best thing to having a step of dentin is to have one of 
cement. The cement serves the purpose of a non-conducting lining 
and a support for the metal filling. 

Lower bicuspid cavities deserve special mention inasmuch as they 
are of different form from the uppers. Proximal decay in lower first 
bicuspids which have low lingual cusps must be prepared as the ante- 
rior teeth. The groove between the cusps is rarely defective in the low 
cusped variety. In the high cusped variety there are usually two 
pits on the occlusal separated by a ridge of perfect enamel which need 
not be cut through to form the step if the occlusion is not heavy. These 
teeth are often wide enough bucco-lingually to permit of the whole 
cavity being dovetailed. The lower second bicuspids demand more 
resistance form, and even though there is a good transverse ridge it 
should be cut across to get enough resistance and retentive form to re- 
tain a large proximal filling. 

In special large mesio-occlusal cavities in upper molars there 
is often some difficulty in managing the mesio-buccal cusp which 
has become undermined. The cusp is usually high and not well 
supported by dentin. If a fissure should run over the buccal from the 
central fossa then there is no doubt about what should be done. Cut 
the whole cusp down with a stone as far distally as the central groove. 
It should be cut low enough to leave room to be covered with suffi- 
cient bulk of filling material to bear the stress of mastication. /\nd 
if it be cut further rootwards as it approaches the central groove 
giving it a general slant to that portion of the cavity it will help to resist 
the tipping stress on the filling. The same method of managing the 
disto-lingual cusp will often add to the retention of the filling and re- 



212 



PREPARATION OF CAVITIES FOR FILLINGS. 




Fig. 185. 




Fig. 186. 



move a weak cusp which is likely to be fractured. Mesial cavities 
in lower molars occasionally involve one of the cusps and need the 
same treatment. (Fig. 185.) 

There is a class of cavities in molars which is often puzzling to the 
beginner. They occur as the result of defective enamel over the whole 
occlusal surface. Caries often ceases after the whole 
enamel surface is stripped off. There are spots of 
penetration but for which they might not need opera- 
tive interference. The pulps are alive and apparently 
normal and the patient under fifteen years of age. It 
is mostly considered wise not to devitalize such pulps 
if they can be retained alive. Grind off any project- 
ing spiculae of enamel. Remove the decayed tissue with spoons and 
if hard remove with large round burs. The only force which is liable 
to dislodge a filling from such a tooth will be a lifting one. 
To overcome this and to keep the filling from being 
forced off the end of the tooth cut a continuous groove 
with an inverted cone bur all the way around the tooth 
about midway between the enamel and the probable 
location of the pulp. A groove made with such a bur 
will have undercut enough to resist the lifting stress. 
If a groove cannot be cut all the way round, good sized pits may be 
cut at the four corners. These will give sufficient hold for a filling 
if it is not built too high. (Fig. 186.) 

THE MANAGEMENT OF LARGE PROXIMO-OCCLUSAL CAVITIES IN 
PULPLESS BICUSPIDS. 

Bicuspids are so narrow mesio-distally and the pulp cavity is so 
situated in the crown that when the necessary cutting is done to re- 
move the pulp from a proximo-occlusal cavity there is little dentin 
left to support the cusps. It usually happens that if a bicuspid has 
decayed deeply enough in one surface to involve the pulp the opposite 
surface is also defective. This increases the weakness of the cusps. 
With the present knowledge of inlays it is hardly ever advisable to 
fill such bicuspids with gold foil. The malleting of so large a filling 
is sufficient to endanger the walls by wedging the gold between them. 
Very occasionally a post might be inserted in the root canal of a bi- 
cuspid to act as a support to a gold filling. Such a post is more ser- 
viceable in lower bicuspids where the transverse ridge is not often de- 
fective and the post serves for retention without cutting a step across 
the occlusal. 



THE TECHNIQUE OF INSERTING A SCREW POST. 213 

THE MANAGEMENT OF LARGE CAVITIES IN PULPLESS MOLARS. 

The secret of success in filling large cavities in molars is to cut 
away the enamel freely. Leave as little enamel exposed to occlusion 
as possible. Grind it low enough to be well covered with filling ma- 
terial. Enamel exposed to occlusion in a pulpless molar must be sup- 
ported by a large bulk of dentin or failure is certain. Posts screwed into 
the root canals often assist in supporting a large proximo-occlusal 
filling which would otherwise have to be supported by cutting deeply 
into the dentin of the tooth, thus unnecessarily weakening the whole 
structure. Large cavities in the lower molars rarely need a post for 
the retention of the filling. The pulp chamber may be used for this 
purpose by cutting a groove around its walls at the base. The bulk 
of filling in the chamber will be strong enough to resist any tipping 
stress and the undercut will resist the lifting force. 

THE TECHNIQUE OF INSERTING A SCREW POST. 

The technique of inserting a screw post into a root canal for the 
purpose of supporting a filling or a tube for a jacket crown is simple 
and yet has to be done a few times to gain speed and get the best re- 
sults. The screw posts which are the most suitable have square heads 
with a tapering thread as a screw nail. The thread is sharp and will 
cut into the dentin as it is forced into the canal. Select the proper 
size of post, ream the canal slightly smaller than the post. Screw the 
post in and out a couple of times. Mark the point on the post when 
screwed into place at which it should be cut off to be properly covered 
with filling material. Remove the post, nick it deep enough with a 
file so as it will twist off when fully twisted down to place after being 
dipped into soft cement or chlora percha. A post to be of service 
should not extend through the filling nor yet be so short that the fill- 
ing cannot be thoroughly packed around it. If the post is intended 
to resist a lifting force that portion of it which is in the filling should be 
riveted to form a head on it. There is always some danger of splitting 
a root by screwing a post in too tightly. 



CHAPTER XI. 
THE TREATMENT OF SENSITIVE DENTIN. 

BY J. P. BUCKLEY, PH. G., D. D, S. 
GENERAL CONSIDERATIONS. 

It is claimed by the best authorities that "in the normal condition 
dentin should be without sensation; and that the source of sensitive 
dentin, or of impressionable pulps, lies in their continued subjection 
to irritation by which responsiveness is developed" (Barrett). This 
view is, I believe, generally conceded to be correct by all who have 
given this subject their attention. It is true that in the preparation 
of cavities for fillings we find few teeth the dentin of which is without 
sensation. This fact is not surprising, nor can it be construed as 
being contrary to the statement that normal dentin is not sensitive, 
when we remember that there are few teeth in the mouths of patients 
demanding the services of the dentist, the dentinal fibrillar and pulps 
of which have not been subjected to continued irritation. 

In the discussion of means and methods by which the sensitiveness 
of the dentin can be allayed I shall not attempt to enter into the 
details of many histologic and pathologic phenomena which are 
certain to arise in the consideration. of the therapeutics of this subject; 
but shall confine myself largely to the drug aspect. 

It is desirable at the outset that the reader should understand 
and appreciate the fact that there is no other one source of failure in 
operative dentistry so great as the improper preparation of the cavity. 
This result does not always follow because of ignorance on the part 
of the operator of the principles involved in cavity preparation, but 
oftentimes because the patient will not permit, or the operator does not 
feel justified in inflicting, the pain necessary in carrying out those 
principles. 

The sensitiveness of the dentin can be obtunded in no small degree 
by the use of various therapeutic agents; and I might state that there 
are few operations which we are called upon to perform wherein the 
patient will appreciate our efforts more than in this by applying drugs 
and remedies for the mitigation of pain. But in order to apply 
intelligently and successfully any remedy, whether it be a drug or an 
agent, to the dentin and thereby obtund the sensitivity of the dentinal 

215 



2 10 THE TREATMENT OF SENSITIVE DENTIN. » 

fibrillar without endangering the vitality of the pulp itself, we must 
be familiar with several factors or conditions, which I cannot with 
propriety here discuss, in detail at least. For instance, a thorough 
knowledge of the anatomic and histologic structure of the tooth is of 
the highest importance, as is also a knowledge of the pathology, 
not only of the hbrillae, but of the pulp tissue as well — the changes 
which these structures are capable of undergoing if unduly irritated 
by the application of the remedy employed. Still another factor of 
equal importance, and one which more directly relates to the phase of 
the subject under consideration, is a knowledge of the pharmacologic 
action and the therapeutic application of the drugs and remedies used 
for this purpose. 

The tendency in dentistry as well as in medicine today is towards 
rational therapeutics. Empirical methods of treatment are being 
rapidly relegated to the past. Before using a drug or an agent for 
allaying the sensitiveness of dentin, or for any other purpose, we 
should know what action to anticipate from its employment. This is 
not too much to expect from the trained dental practitioner of today. 

THERAPEUTICS. 

The remedies suggested for obtunding sensitive dentin have been 
many and varied. I shall discuss only those which, from clinical 
experience, have proved of sufficient value to merit consideration; 
and for convenience of study, will divide them into four general classes. 

I. Physical Agents. — Any agent, whether heat, cold, light, 
electricity, or any influence whatever, if employed in the treatment 
of a diseased condition, is a remedy. There are some physical agents 
by the proper use of which the sensitiveness of dentin can, in a measure, 
be obtunded. 

(i) Heat. — The application of dry heat to a sensitive cavity, 
especially in conjunction with a dehydrating agent such as absolute 
alcohol, is always an aid; and this is accomplished by means of heating 
dry air, and gently directing a current of air thus heated into the 
cavity which has been isolated by the rubber dam and moistened with 
the dehydrating agent used. Care must be taken not to primarily 
cause pain, otherwise the object of using the agent would be defeated. 

Several apparatuses have been devised for heating the air. Dr. 
Rudolph Beck, of Chicago, has recently perfected a convenient electrical 
device by means of which compressed air can be heated as it passes 
through. Other such devices are on the market. In the absence of 
any of these the chip-blower can be employed; however, with less 



THERAPEUTICS. 2 1 7 

satisfaction. Inasmuch as heat is used in conjunction with another 
and more important class of remedies, I shall refer to this agent later. 

(2) Cold. — A lesser degree of heat, commonly designated cold, 
is another physical agent sometimes employed for the purpose of 
desensitizing the dentin. Heat may be abstracted from the tooth 
structure by spraying the cavity with a highly volatile liquid, like 
ether, rhigolene, or ethyl chlorid. In the use of these agents, advant- 
age is taken of the physical law that a solid in changing its form to a 
liquid, or a liquid in changing its form to a vapor or gas, must abstract 
from the thing to which it is applied, a certain amount of heat in order 
to effect the change. Ether, or combinations containing ether, and 
ethyl chlorid, both used as sprays, have proved valuable in some 
instances, especially shallow cavities near the gum the dentin of which 
is difficult to obtund by the usual methods employed, and to which 
reference will be made later on in this chapter. 

A precaution to be taken to prevent primary pain in applying this 
remedy, is to fill the cavity temporarily with stopping, and direct the 
spray first on this and surrounding parts, after which the stopping can 
be removed and the spray directed into cavity without any appreciable 
pain. The degree of refrigeration must not be carried to the point 
of having a possible deleterious effect subsequently upon the pulp 
or gum tissue. 

(3) Light. — A form of energy called light has recently been brought 
forth as having a peculiarly favorable effect upon hypersensitive 
patients. In one method the rays of light are colored by passing 
through a blue glass. This is accomplished by darkening the room 
and employing a blue bulb (16 or 32 c.p.) on an ordinary electric 
socket. Whether the light acts locally, or affects the vision and thus 
the general nervous system, has yet to be demonstrated. The result 
of the author's experience with this agent thus far has not been encour- 
aging.' It is true that light differs in effect from heat, though both 
come from the same heated body. This phenomenon is observed in 
the action of light on certain chemicals; for example, the silver salts, 
some of which are used as obtundents, undergo a chemical change 
when exposed to sunlight or luminously hot bodies. 

(4) Electric Current. — This agent has been employed as a means 
of carrying certain drugs into the dentin and pulp tissue for obtundent 
purposes. The method is called cataphoresis; but because of the 
expensive and complicated apparatus, the length of time required to 
obtund as well as oftentimes unsatisfactory, and, in not a few instances, 
disastrous results, the method has generallv been discarded. 



2 1 8 THE TREATMENT OF SENSITIVE DENTIN. 

II. Escharotics or Caustics. — Escharotics, or caustics, are agents 
that destroy or disorganize the tissue upon which they act. Any 
drug or agent, then, which will cauterize the dentinal fibrillar, will 
obtund sensitive dentin. There are many drugs, however, belonging 
to this class that cannot be used for this purpose because of their 
deleterious effect upon both the tooth structure and the pulp tissue. 
For instance, the strong mineral acids will disorganize the protoplasmic 
dentinal fibrillar; but they will also disintegrate the inorganic structure 
of the tooth. Arsenic trioxid has a specific poisonous action upon the 
fibrillae, but there is no known means of preventing the same deleterious 
effect upon the cells of the pulp tissue. 

The most valuable escharotics for desensitizing the dentin are: 

Phenol, Trichloracetic acid, 

Zinc chlorid, Silver nitrate. 

It must be noted that, while these agents will obtund, the ultimate 
result is too often produced, with the possible exception of phenol, 
at the expense of quite as much suffering as they save. 

Phenol has local analgesic properties besides that of cauterant, 
and will, therefore, be discussed under another and more important 
class of agents. 

Zinc chlorid in various strength solutions can be used to advantage 
in a class of cavities where the decay or softened dentin does not 
extend too close to the pulp. Zinc chlorid coagulates albumin and 
in the process hydrochloric acid is liberated. For this reason the 
application of strong solutions is painful and should not be employed 
in deep cavities unless the irritating action of the agent is modified. 
This can be done to a marked degree by selecting alcohol and chloro- 
form as the vehicle in which to make the solution. 

A useful formula is here given: 

1$ — Zinci chloridi, gr. xx 

Alcoholis, f . 3 iv 

Chloroformi, q. s. ad, f. § j — M. 

Sig. — Apply to the cavity on a small pledget of 
cotton and gently evaporate to dryness. 

Note: If the zinc salt does not make a clear 
solution in the alcohol it indicates that 
some of the salt has been oxidized; the 
solution can be cleared by adding one 
drop of hydrochloric acid. 

Trichloracetic acid in concentrated solution causes considerable 
pain when first applied to a sensitive cavity, therefore defeating the 



THERAPEUTICS. 219 

object of its use; but in a 10 or 15 per cent solution it produces but 
little pain or inflammatory reaction. In this strength it can be em- 
ployed; but not always with satisfactory results. 

Silver nitrate is perhaps the only known prophylactic for decay. 
In the posterior part of the mouth where the cementum is exposed 
to external influences and thus sensitive, or in shallow cavities, especi- 
ally in children's teeth, the use of this drug, in the solid pencil form 
or in various strength solutions, will be found valuable, both as a 
means of reducing the sensitiveness and preventing further ingress of 
caries. As an agent for obtunding the sensitivity of the dentin in an 
ordinary cavity, it should not be considered for various reasons. 
When the agent is employed for the purposes above mentioned, the 
cavity, after the application, should be kept free from saliva for a 
few minutes, and, if possible, exposed to sunlight, thus decomposing 
the silver salt as referred to in this chapter under the subject of light. 
A solution of sodium chlorid should always be at hand when using 
silver nitrate, and in case any of the latter agent should accidentally 
get on the mucous membrane of the patient's mouth its action can be 
checked at once by rinsing the mouth with this antidotal solution. 

III. Local Anodynes or Local Anesthetics. — A local anodyne is 
an agent which, when applied to a part, relieves pain. A local anes- 
thetic is an agent which, when applied, produces insensibility to pain 
in that particular locality. According to Long, it rather produces a 
condition of analgesia, which means the absence of sensibility to pain, 
as distinguished from true anesthesia, the absence of all sensibility. 

In the judicious use of agents belonging to this class the author 
firmly believes will ultimately be found the surest and safest road to 
success. The following agents, or a combination of two or more, 
will be found to be of the utmost importance: 



Cocain, 


Phenol, 


Menthol, 


Ethyl chlorid. 


Oil of cloves, 


Ether, 


Eugenol, 


Chloroform. 



Cocain is one of several alkaloids, this being by far the most im- 
portant, obtained from the leaves of Erythroxylon Coca, a plant 
indigenous to Peru and other South American states. Both the 
alkaloid, cocain, and the alkaloidal salt, cocain hydrochlorid, are 
used in various ways for obtunding sensitive dentin. The alkaloidal 
salt was formerly recognized by the United States Pharmacopeia as 
cocain hydrochlorate ; but in the last edition (1900) it is called cocain 
hydrochlorid. An important physiologic property of cocain to be 



2 20 THE TREATMENT OF SENSITIVE DENTIN. 

remembered here, is its power, when applied directly to the mucous 
membrane or when injected or forced into the pulp tissue, of inducing 
a condition of analgesia in the part by paralyzing the sensory nerve 
filaments. In addition to this it causes a blanching of the part which 
is subsequently followed by congestion. It should also be remembered 
that pharmacologists have proved, beyond a doubt, that cocain is a 
general protoplasmic poison; that muscles as well as nerves and nerve- 
ends cease to contract or to conduct stimuli when they are exposed 
to even dilute solutions of the drug. The only reason that the delete- 
rious effect is more noticeable upon nerve than upon other kinds of 
tissue is that here we are dealing with the medium of sensation and 
expression. 

The author deems it wise to call attention to these well-established 
physiologic, pharmacologic and pathologic facts, for many instruments 
have recently been devised for forcing various strength solutions of 
cocain hydrochlorid, not only into the dentinal tubuli, thereby paral- 
yzing the nbrillae, but into the pulp proper, anesthetizing this organ 
as well. In view of these facts it would appear that we are never 
justified in completely anesthetizing the pulp of a tooth for the purpose 
oj painlessly preparing a cavity therein. Therefore under the subject 
of cataphoresis in this chapter, little was written; and for the same 
reasons, the method of anesthetizing the pulp by high pressure anes- 
thesia, for obtundent purposes only, will not be considered. Both 
of these methods will be discussed in a subsequent chapter on pulp 
removal. 

Cocain and the alkaloidal salt, cocain hydrochlorid, are safe and 
valuable agents for obtunding sensitive dentin, if confined to the 
dentinal structure of the tooth. Frequently in deep-seated cavities, 
especially in children's teeth, the sensitiveness can be completely 
overcome by sealing in the cavity for a day or two a creamy paste 
made by mixing the alkaloid cocain with liquid petroleum. The 
revised edition of the United States Pharmacopeia now recognizes an 
oleate of cocain (5 per cent) , which can be used for this purpose. The 
paste or oleate should cover the entire surface of dentin which we sub- 
sequently expect to excavate. Good results can also be immediately 
obtained by the use of the following remedy: 

1^ — Cocainae, gr. xx 

Chloroformi, f. 5 ij 

Etberis, q. s. ad, f. o j — M. 

Sig. — After the rubber dam has been adjusted, 
apply to the cavity on a small pledget of 
cotton and evaporate to dryness. 



THERAPEUTICS. 221 

In the use of this remedy, advantage is taken of the physical law 
previously referred to in this chapter under cold. As the volatile 
liquids, ether and chloroform, evaporate, a certain amount of heat 
is abstracted from the tooth structure, and a coating of the alkaloid, 
driven to an extent into the dentin, is left in the cavity. This remedy 
will not completely obtund all sensitive dentin, but its use will be a 
material aid. 

There can be no objection in favorable cases, provided the dentin 
has been previously sterilized, to using aqueous solutions of cocain 
hydrochlorid with uniform pressure over the entire area of the cavity, 
thus forcing the anesthetizing solution an equal distance into the 
dentin. This is an extremely difficult thing to do without forcing the 
solution at some more favorable point in the cavity through the tubuli 
and into the pulp. However, there are cavities where good results 
can be accomplished by the careful use of this method. In some 
cases of cervical cavities good results can be obtained by hypoder- 
mically injecting a i or 1.5 per cent solution of cocain hydrochlorid 
into the pericemental membrane somewhere near the apex of the 
root. This practice should not be generally recommended. 

Menthol, a stearopten obtained from the essential oil of pepper- 
mint, can be substituted for the cocain in the above prescription with 
ether and chloroform, and used in exactly the same manner. An 
oily liquid (mentho-chloral) can be formed by heating together over 
a water-bath or rubbing in a mortar, an equal amount of menthol 
and. chloral. This remedy will be found efficacious by sealing in the 
cavity for a few days. 

Oil of Cloves. — A profound analgesic effect can be produced upon 
sensitive dentin, especially in deep-seated cavities, by using oil of 
cloves and heat in the following manner: After carefully desiccating 
the dentin by means of warm alcohol and gentle heat, a pledget of 
cotton saturated with oil of cloves should be placed in the cavity and 
a current of heated dry air directed thereon until the cotton is nearly 
dry. This should be repeated as often as the case demands. 

Eugenol, an oily product, is the chief constituent of oil of cloves 
and can be used in the same manner as above described. 

Phenol. — It is gratifying to the author to know that in the last 
revision of United States Pharmacopeia (1900), the publication of 
which appeared Sept. 1, 1905, the product heretofore erroneously 
called carbolic acid has been recognized by its correct name, phenol. 
This agent can be substituted, with equally good results, for the oil 
of cloves or eugenol as described in the foregoing method. Care 



THE TREATMENT OF SENSITIVE DENTIN. 

should be taken here, however, in directing the heated air so as not to 
cause the fumes of phenol to escape on the patient's face. Oil of 
cloves, eugenol and phenol are three true local anodynes, and any one 
of which, if hermetically sealed in a cavity for a few weeks, will check 
the continued irritation of the fibrillar and pulp, thus aiding nature 
to restore these structures to their normal condition when they should 
not be responsive. By this means, then, the sensitiveness of the 
dentin can also be allayed. 

Ethyl c hi or id, ether and chloroform, by their rapid volatility, 
produce a condition of analgesia, thereby obtunding sensitive dentin, 
as previously explained in this chapter under cold. 

IV. General Anodynes or Analgesics. — General anodynes or anal- 
gesics are remedies which relieve pain without necessarily inducing 
unconsciousness or general anesthesia. They may accomplish their 
object by acting upon the perceptive centers of the brain, the afferent 
paths in the spinal cord, or the peripheral nerve through which the 
painful impression is transmitted (Stevens). 

In order to do permanent work for certain highly nervous patients, 
it is sometimes necessary to resort to the administration of this class 
of drugs. The agents largely used for this purpose are: 

Opium, Nitrous oxid, 

The bromids, Chloroform. 

Opium is a most powerful analgesic, and while there are some 
dental conditions where this drug, or its chief alkaloid, morphin, is 
truly indicated, it ought not, in the author's judgment, to be given for 
the treatment of sensitive dentin. 

The bromids of potassium, sodium and ammonium are valuable 
drugs in certain cases. Perhaps there is no drug which will quiet 
a nervous patient more readily, when the nervousness comes purely 
from fear or dread, than potassium bromid, which is the represen- 
tative of this class. In such cases, where it is deemed necessary, the 
following prescription will prove helpful: 

T$ — Potassii bromidi, o jss 

Syrupi sarsaparillae comp., f. 5 iij — M. 

Sig. — Take a tablespoonful in water after meals the 
day before coming to the office. 

Nitrous Oxid. — There are several apparatuses on the market 
by which nitrous oxid gas can be administered through the nose. 
It is possible with such an apparatus to carry the patient just to the 
analgesic stage, and hold him there until a sensitive cavity has been 



THERAPEUTICS. 223 

painlessly prepared. In cases where the operator feels that it is 
necessary to resort to this method, good results can be accomplished. 

Chloroform. — With the patient in the upright position, chloroform 
can be carried to the analgesic stage and sensitive cavities prepared. 
Most authorities agree, however, that chloroform should not be 
administered unless the patient is in the recumbent position, and that 
the analgesic stage is the most dangerous. Death has been known 
to occur suddenly, after a few inhalations, in cases of marked idio- 
syncrasy against the drug. 

The author would not suggest the use of chloroform for this 
purpose. 

In closing this chapter, may I say that most patients who repose 
confidence in the operator, are sensible and are willing to stand some 
pain in the preparation of cavities in their teeth. With a true running 
engine, a steady hand, a sharp bur, and with the aid of some of the 
many remedies herein suggested, the operator ought not to expect 
nor to ask the patient to stand more than a small amount of pain in 
the preparation of the most sensitive cavity. 



CHAPTER XII. 

FILLING MATERIALS: THEIR CHARACTERISTICS, 

INDICATIONS FOR THEIR USE AND THE 

METHODS OF MANIPULATION. 

BY ALFRED OWRE, M. D., C. M., D. M. D. 

The dentist of today is, perhaps, more occupied with the treat- 
ment of caries, both in theory and in practice, than with any other 
branch of his profession. Although we recognize, in the prevalent 
custom of treatment by filling, only a provisional substitute for some 
more nearly perfect one at which, in our present stage of development, 
we have not yet arrived, it behooves us, until we shall have outgrown 
it, to study closely its methods and materials. 

In the discussion of materials we are confronted by the fact that 
in the very nature of things there can be no one substance suited to all 
cases. There is, however, for every case a suitable material, or one 
which can be continued in use as such until, in our pursuit of the ideal, 
we progress to something more effective. 

To acquire the art of filling teeth seems at the outset an Alpine 
task. A thorough understanding of the properties of various neces- 
sary materials will reduce difficulties immensely, just as in setting out 
for a long climb in the mountains the providing of guides and the 
study of maps will reduce distances and minimize dangers. 

It w r ill be the aim of this chapter to point out as clearly as possible 
the teleological value and characteristic properties of gold, amalgam, 
tin, cement, and gutta-percha. We shall try to suggest when and 
where to apply these materials in filling cavities of teeth to insure 
the highest degree of success; and also to describe the methods of prep- 
aration, insertion, and finish. 

GOLD. 

From the earliest days of dental surgery, gold seems to have been 
considered the filling material par excellence. It occupies a unique 
prominence in operative dentistry. The ancient uses to which it was 
put for royal and religious ornament rendered its more common prop- 
erties familiar to the metal-workers of even prehistoric times. The 
greedy, but persistent, alchemists of mediaeval laboratories have con- 
tributed to modern science the results of their research for "the philos- 
15 225 



2 20 FILLING MATERIALS. 

opher's stone.'' Gold has had, therefore, one great advantage — 
that of familiarity — over the later filling materials whose properties 
were little known and in whose actions scientists were slow to become 
interested. 

The appeal of gold, to primitive man, inhered in its peculiar 
combination of luster and yellow color. This color is deepened or 
raised in tone by the introduction of foreign substances, copper for 
the former purpose, and silver for the latter. In allotropic form 
it is susceptible of alteration to other than the original color. When 
reduced to a finely divided state by precipitation, violet, dark red, 
purple, brown, and even black may be produced. However, when 
burnished or fused, it again assumes its characteristic yellow color. 

Another peculiar property of gold is its extreme malleability. 
In this respect it exceeds all other metals. It can be reduced by 
beating to -3T0V0IF °^ an i ncn m thickness. It also heads the list in 
ductility. A single grain may be drawn out into a wire over five 
hundred feet in length. Both of these properties are modified or ren- 
dered nil by alloying. 

As to the property of hardness, gold, when pure, lies between 
silver and aluminum. It is about one-third as hard as diamond. 
This property is generally increased by the presence of alloys, extremely 
small quantities of some elements (bismuth, lead, etc.) having a very 
marked effect, even to rendering the metal capable of pulverization 
in a mortar. 

As regards tenacity, pure gold will hold a weight of seven tons per 
square inch. This property, also, is reduced by the presence of im- 
purities. 

The specific gravity of cast gold is 19.3, which can be increased by 
condensation. In some of its precipitated forms it may be as high 
as 20.3. The difference is accounted for by the annealing in the for- 
mer case. 

In general, gold is weldable in the cold state in proportion to its 
purity; a very minute trace, 1 in 1000, of foreign metal such as silver, 
copper, or platinum, is said not noticeably to interfere with its cohesive- 
ness. This property is usually increased by heating. 

The presence of other metals alloyed with gold renders it more 
susceptible to the occlusion of obnoxious gases. The cohesive power 
is decidedly lessened by surface gases such as ammonia, hydrogen, 
hydrogen phosphide, and sulphurous acid gas, all of which are at- 
tracted to pure gold, but to a greater degree when the metal is finely 
divided than when it is cast. 



GOLD. 227 

In the scale of conductivity, with silver first, at 1000 for both heat 
and electricity, copper is second, and gold third with a register of 548 
for heat, and 730 for electricity. 

Its solubility is proved in aqua regia and in mixtures producing 
nascent chlorine, bromine, and, under certain conditions, iodine. 

The consideration of the qualities essential to a good filling ma- 
terial is a very important one. According to Dr. G. V. Black, the 
chief qualities are: 

Indestructibility in the fluids of the mouth. Adaptability to cavity 
walls. Freedom from shrinkage or expansion after having been 
made into fillings. Resistance to attrition and the force of mastic- 
ation. Of secondary importance are color, non-conductivity of ther- 
mal impressions, and convenience of manipulation. It should also 
be capable of receiving a polish. 

Bearing its constant properties in mind, let us see how gold fulfills 
these requirements. 

There can be no question as to its indestructibility in the fluids of 
the mouth; although iodine discolors it somewhat, it does not cause 
solution. It is highly capable of adaptation to cavity walls. There 
is neither shrinkage nor expansion; but the intermittent forces of mas- 
tication may work, together with the peculiar molecular structures, 
to produce some change in form. The yellow color and high burnish, 
so beautiful in themselves, are, as fillings, more or less of an objection 
from the esthetic viewpoint. The contrast in color between the gold 
and the enamel may be rendered less noticeable by attention to the 
outline form of the cavity. An outline may be varied for the sake of 
grace, without hindering the achievement of artistic results, bearing 
in mind, of course, that the application of gold is not, primarily, 
assumed to be inartistic. Conductivity is a decidedly unfavorable 
property. In regard to the manipulation of gold, we may say that, 
in general, it is difficult, and demands sustained effort. It is generally 
acknowledged that success with this material exacts close application 
and prolonged study. As to finish, a perfect surface depends only 
upon the gold being reasonably well condensed. 

As to the use of gold, it is not easy to lay down set laws. When 
and where to apply it depend upon a close study of general conditions 
and upon the extent to which the operator's instinct for the eternal 
fitness of things has been cultivated. No aspect of dentistry demands 
keener judgment and finer appreciation of practical and esthetic 
values. Moreover, the physical condition and idiosyncrasies of the 
patient constitute a large factor in the problem. The age and state 



228 FILLING MATERIALS.. 

of health, both general and local, must be taken into consideration. 
Mental traits, as well, will be weighed by the tactful dentist, since the 
immature mind, and that which is under imperfect nervous contro 
must be met with special resources. 

It must be borne in mind that in man as in other animals the period 
of plasticity is the age of education. Organization and education, 
physical and mental, have sometimes reached a stage of balance early 
in life. When this happens, rather extensive gold fillings may be made 
for patients between the ages of ten and sixteen years. 

Between twelve and eighteen, the age of adolescence, the powers 
of the body develop at a lower rate than those of the mind; and it 
would be unwise to attempt the insertion of large gold fillings unless 
the entire system of the patient be adequate to the strain. 

As the patient advances in years, the physical and nervous re- 
sistance must not cease to be a matter of careful consideration. If 
this resistance be below par, or if all extra energy be needed to nurse 
some disorder, it is best to postpone large gold operations. 

Locally we have many things to consider, such as conditions of 
the peridental membrane, the extent and acuteness of decay, the 
structure and strength of cavity walls, occlusion, wear and tear, the 
position of the tooth, accessibility, and possibly also the past hygiene 
and care of the mouth. 

It is quite needless to say that no gold rilling should ever be at- 
tempted in any tooth when there is manifest pericemental inflammation. 
The slight loosening of the tooth as a result of deposits, or of wear and 
tear, need not prohibit the insertion of gold; but if any great degree of 
loosening has taken place, gold is generally contra-indicated. Whether 
the membrane is abnormal or not, its resistance should be a guide. 
If caries is rampant, it is often advisable not to consider gold until 
more favorable conditions, or a period of immunity, ensue. 

The firmness* of the cavity walls may be insufficient to withstand 
the force necessary for the proper introduction of gold, especially 
if the strength of the bite is in the neighborhood of 175 pounds. Many 
malleted gold fillings fail in strong occlusions. They may also fail 
where the area of masticating surface has been lessened by extractions 
of molar teeth. In this latter case, it often occurs that proximo- 
incisal fillings have been literally pounded out, owing to the excess of 
work performed by the anterior teeth. 

In regard to position, the tooth may be inclined to such a degree 
as to render gold difficult to insert, and, in consequence, preferably 
omitted. 



GOLD. 229 

The use of gold need not be restricted to any particular teeth, for 
instance, as has been often suggested, to the ten anterior teeth. It 
would be more scientific, and decidedly more practical to say that, 
other things being equal, we can use it wherever there is sufficient 
accessibility. So far, then, it becomes the ideal. 

Much has been said about this material. In fact, it would seem 
that nothing more remains to be said either for or against it. When 
we consider that the future preservation of the teeth depends upon 
the extent to which recurrence of caries can be prevented, and normal 
conditions and functions otherwise restored, we naturally seek a fill- 
ing material which will as much as possible further these aims. 
Statistics have been published showing that the average life of a gold 
filling is three years. Just so long as gold is used indiscriminately, 
and by all kinds of operators, will we have such figures. 

But these are not the statistics by which we wish to be influenced. 
It debases our own standards, and works injustice to the best men in 
the profession of dentistry — those who are most influential, and who 
make up a very large proportion of the total number — to obscure their 
results by fusing with them the results of the incapable, and then strik- 
ing an average. Such statistics are misleading. It would be much 
more to the purpose to take account only of those men who are pre- 
eminently fitted to practice dentistry. Such men are honest enough 
to acknowledge failures wherever they occur, and if data were gathered 
exclusively from them, some reliable figures would exist upon which 
changes could be based when it is found that the percentage of failures 
is becoming too high. 

Not to go any further with this discussion, we may, for the moment, 
rest upon the statement that success hinges upon careful judgment 
in the selection of cases, as well as upon manipulation or technique 
of insertion and finish. 

In all discussions of the subject, so much is said as to the import- 
ance of purity in gold, that it has been thought best to quote in full the 
Roberts- Austen refining process as given in Rose's The Metallurgy 
of Gold: 

Gold assay cornets, from the purest gold which can be obtained, are dis- 
solved in nitrohydrochloric acid, the excess of acid expelled, and alcohol 
and chloride of potassium added to precipitate traces of platinum. The 
chloride of gold is then dissolved in distilled water in the proportion of 
about half an ounce of the metal to one gallon, and the solution allowed 
to stand for three weeks. At the end of this time the whole of the pre- 
cipitated silver chloride will have subsided to the bottom, and the super- 



23O FILLING MATERIALS. 

natant liquid is removed by a glass siphon. Crystals of oxalic acid are 
then added from time to time, and the liquid gently warmed until it be- 
comes colorless, when precipitation is complete, a point reached in three 
or four days if ten-gallon vessels are used. The spongy and scaly gold 
so obtained is washed repeatedly with hydrochloric acid, distilled water, 
ammonia, and distilled water again, until no reaction for silver or chlo- 
rine can be obtained, after which it is melted into a clay crucible with 
bisulphate of potash and borax, and poured into a stone mold. Lack 
of care in any one of the operations will result in gold containing one or 
two parts of impurity in ten thousand. 

If further purity is desired, the gold may be redissolved and re- 
precipitated until satisfaction is attained. 

Gold comes to us from the manufacturer in two varieties, foils 
and crystals. A complete description of the manufacture of foil oc- 
curs in an article entitled "Gold Beating" in the Encyclopedia Brit- 
tanica. 

The sheets are usually four inches square, and the number by which 
each one is identified corresponds to the number of grains in the sheet; 
e. g.j in No. 4 foil each sheet weighs 4 grs., and so on up to No. 100, 
or higher. Above No. 20, the sheets are rolled out instead of beaten. 
They may be had smooth or corrugated. 

Foils may be classified according as they lack or possess the property 
of cohesion. They are non-cohesive, semicohesive, or cohesive. 
Non-cohesive gold is made so by surface treatment, and although the 
process is not made public, we know that we can render pure gold non- 
cohesive by exposing it to ammoniacal gas.* The semicohesive golds, 
and some of the non-cohesive, can be made cohesive by annealing, 
which demonstrates that surface treatment had consisted, in this in- 
stance, of subjection to a volatile gas. 

Some non-cohesive foils are permanently so, and the gases covering 
the surface are probably of the sulphur or phosphor groups, which can- 
not be volatilized by heat, but condense upon the surface. 

Foil has been used for about a century, chiefly in a non-cohesive 
state. The discovery of its cohesive property, about fifty years ago, 
marks an era in the history of operative dentistry. It has made con- 
tour possible in its broadest sense, and the resulting advances are of 
tremendous importance. That the possibilities are not yet exhausted 
is another point which should encourage the profession towards 
progress. 

The crystals of gold are obtained by precipitation. The manufac- 

*Dr. G. V. Black, Dental Cosmos, Vol. 17. 



GOLD. 231 

turers guard their trade secrets so well that we do not know what pre- 
cipitating agent is used. Oxalic acid, purified sulphurous acid gas, 
and other chemical reagents can be used, but at present these are largely 
replaced by electrolytic methods. There are on the market several 
variations of these forms, of which the fiber-like crystals are generally 
to be preferred. It is very probable that the crystals have a higher 
specific gravity, since they have never been subjected to fusion. They 
are usually sold in the cohesive state. Among qualities decidedly in 
their favor is a plasticity which renders them easy to manipulate. 

There has been, and still is, some prejudice against gold in this 
form, owing to a variable quality which can be accounted for, in a 
measure, by the fact that crystals are more easily contaminated. 

Although methods of preparation have been more or less faulty 
in the past, modern methods have given us a fairly reliable product, 
with the result that crystals have increased in use. 

The dentist should procure a gold which is experimentally known 
for its good qualities; but he must always be on the lookout lest un- 
scrupulous manufacturers permit deterioration. 

There is a variety of ways in which the dentist can shape foil as 
wanted, and to suit the various cavities: the ribbon, mat, cylinder, 
pellet, or rope. In some of these shapes it can be bought ready 
prepared. 

The ribbon is formed by taking as much as is required of a sheet 
of gold and, by repeated folding, reducing it to the desired width. 
The mat is made by simply folding the width of the ribbon upon itself 
according to size wanted; cylinders, by rolling the ribbon upon a flat 
broach. The pellet may represent from ^ of a sheet upwards, rolled 
to a loose ball between the ends of the fingers. The ropes or rolls are 
made by rolling a part of the sheet between the thumb and forefinger, 
or between two napkins. The heavier foils need only to be cut into 
strips of suitable size. 

Dr. Black recommends keeping the gold in a compartment where 
ammonia is present, thus rendering it non-cohesive, and protecting 
it from other gases. If desired, cohesiveness may, of course, be re- 
stored by annealing. For this purpose, gas, alcohol, or electricity 
may be used as a means of heat. Gas, alcohol, or any open flames 
are objectionable on account of contaminations, grain alcohol being 
the least so. A sheet of mica or a porcelain tray may be used between 
the flame and the gold, thus reducing the objection to a minimum. 
The electric annealer is by far the best.* It distributes the heat evenly 

*The Custer electric annealer is generally recognized as the superior make. 



2 \2 



FILLING MATERIALS. 



and at varying degrees. It also does away with handling the gold 
during the annealing process. 

In discussing the insertion of gold, it is assumed that the cavity 
is prepared according to the principles laid down in chapter on the 
preparation of cavities for fillings. 

Non-cohesive gold is not used very frequently for the entire cavity, 
since surrounding walls are necessary to its insertion, and in this day 
of specialization few men are enabled to acquire skill in its application. 
There seem to be scarcely enough points in its favor to compensate 
for the time consumed in acquiring this skill. Its use is limited to 
simple cavities. As no union of the gold laminae takes place, the wedge 
principle of insertion must be depended upon. 

The cylinder is the best shape to use for this work. It should be 
somewhat longer than the depth of the walls against which it is to be 
forced. Several cylinders are placed endwise in the cavity, and forced 
against each surrounding wall with a wedge-shaped instrument, thus 
leaving a space in the center within which are placed other cylinders 



Figs. 187. 





191 



i93- 



f 
194. 



i95- 



9 



196. 197. 



until it is impossible to make room for any more. The whole mass is 
then condensed by a suitable plugger point, the outer ends thus being 
forced as far as possible into the cavity. The cylinders should always 
be of sufficient length, so that, when tightly wedged and finally con- 
densed, the cavity will be over full. 

It is claimed for the non-cohesive filling that when it is used water- 
tight margins are more perfectly made, and fillings are inserted with 
greater dispatch, provided the peculiar skill demanded for its manip- 
ulation has been acquired. 

Filling cavities with cohesive gold, an art which requires years 
to master, demands less theorizing than demonstration, more actual 
experience than ponderous texts, so decidedly practical are all its 
details. Success is based upon many considerations, to some of which 
reference has already been made. The importance of modern cavity 
preparation cannot be too strongly emphasized, for upon it much de- 
pends. Separation of the teeth for the purpose of accessibility, and 
fixation to render the attachment tense, are also of moment. 



GOLD. 



*33 




$ 



(T> 



frn ^ 



Figs 



199. 



is also well to re mem- 
condensing area of a 



rr^ 



A large variety of plugger points is needed to fill special wants, 
but for ordinary purposes the dentist confines himself to a few forms 
with which he has become thoroughly familiar. The illustrations, 
Figs. 187 to 197, will be referred to 
as occasion demands. 

The shank of each plugger should 
bend a few degrees so that it will not 
interfere with the operator's view of 
the working point. The modern law 
of accessibility in cavity preparation 
has limited the modifications in the 
shank to only three besides the 
above; namely, the bayonet, the right 
angle, and, for special work, the 
complete reverse. (Figs. 198, 199, 
200, 201, 202.) 

All should be finely serrated. It 
ber that .5 mm. is about as large 

point as should ever be used. The force necessary to con- 
dense gold with larger areas is generally unbearable, and is 
also liable to cause bridging over or imperfections in solidity. 
Small points which pierce the gold should not be used. 

Another factor to consider is the manner of obtaining 
condensing force. Hand pressure is the simplest. The 
hand mallet, the automatic and other mechanical inventions, 
are all applied more or less. Dr. Black recommends the 
mallet in the hands of an assistant as the best means. It 
should be a rule always to place the gold where wanted in 
the cavity, and closely pack its laminae with a light hand 
pressure, then mallet until the required solidity is obtained. 
The force should be so directed as to distribute itself evenly 
over the tooth- attachment; that is, toward the long axis. 
This causes the least inconvenience to the patient. 

Perfect adaptation to cavity walls and margins, and 
adequate condensation, are the chief objects of attainment 
in these fillings. Both are interfered with by over-annealing. 
In fact, the very first pieces introduced in the cavity may 
be unannealed cohesive gold, which secures more easily, 
and with more certainty, the above-mentioned adaptation. 
Masses of gold, if too large, cannot be properly placed and condensed. 
For starting the filling, -gV of a sheet No. 4 foil is quite sufficient, or 



Fig. 202. 



234 



FILLING MATERIALS. 



an amount that may be readily anchored into one angle of the cavity. 
It is generally not advisable to use a mass of gold the bulk of which is 
more than one-third the size of the cavity. 

A solid plug is obtained only by carefully welding each newly added 
mass to that already in the cavity. In doing this, the force exerted 
in manipulation must not in any way distort the filling or interfere 



V 



ir^J 



Fig. 203. 




Fig. 204. 



Fig. 205. 



Fig. 206. 



Fig. 207. 



Fig. 203. — Axio-mesio-distal plane. Showing gold started. 

Fig. 204. — Axio-mesio-distal plane. Showing floor covered and advance of axial walls. 

Fig. 205. — Axio-mesio-distal plane. Overfull and ready for finishing. 

Fig. 206. — Longitudinal section, Bucco-lingual plane, mesial fourth, through retention 
form of cavity. Showing gold started. Dotted lines represent the outline form of the 
cavity. 

Fig. 207. — Same as Fig. 206. Showing the union complete, and surface brought up. 

with adaptation, but rather be so directed as further to insure adapta- 
tion and stability. The plugger should, therefore, generally proceed 
from the center to the periphery. It is never judicious to exert force 
on thin layers of gold covering flat surfaces. Moreover, in covering 
margins, especial care should be taken to have a good cushion of gold 







Fig. 208. 



Fig. 209. 



Fig. 210. 



Fig. 211. 

Showing gold 



Fig. 208. — Longitudinal section, Mesio-distal plane, Buccal fourth, 
started (as in Fig. 206). 

Fig. 209. — Showing the progression of the gold building after gingival wall has been 
covered. 

Fig. 210. — Same section and plane, but cut through middle of tooth. Showing locking 
of step, and proximal part of filling. 

Fig. 211. — Same as preceding. Gold building complete. 



over the margins, thus avoiding danger of the plugger point coming in 
contact with the tooth tissue. 

In filling a simple cavity, the process of building the gold is illus- 
trated in Figs. 203, 204, 205. Plugger points 187, 188, 191 and 196, 
are used in this class of cavities in the anterior teeth, and as we go 
back into the mouth the bayonet, 194, will also be needed. 



GOLD. 235 

The filling of a complex cavity is best illustrated in the mesio- 
occlusal of a first upper molar. (Figs. 206 to 211.) The axio-bucco- 
and axio-linguo-gingival point angles are first filled, and then the axio- 
gingival line angle is covered, starting from each point angle re- 
spectively, so that the surface represents an angle of 45 degrees 
with the axial or gingival wall, and the latter is built out upon until 
its margin is fully covered. The filling should then proceed swiftly to 
the contact point, and, in doing so, one should as nearly as possible pre- 
serve a flat surface; but the inclination from buccal to lingual may 
vary according to accessibility. For this part of the work pluggers 
187, 188, 192 and 193 are used for starting the filling, and 194, 195, 
196 and 197 for further condensing. The step portion of the cavity is 
started in the same manner as the simple cavity, but instead of building 
up over the missing wall, the operator laps the gold over the proximal 
portion, and builds the whole out until it is overfull. 

The practice of making mesio-occlusal-distal fillings in one opera- 




Fig. 212. Fig. 213. Fig. 214. Fig. 215. Fig. 216. 

Fig. 212. — Mesio-distal plane. Showing the starting of gold. 

Fig. 213. — Same as Fig. 212. Showing progress of gold building and union of incisal 
part with the rest of the filling. 

Fig. 214. — Same section. Gold building finished. 

Fig. 215. — Axio-mesio-distal plane. Showing process of gold building in cavities 
involving angle. 

Fig. 216. — Same section as 215. Gold building finished. 



tion should be discouraged. It is economy in every respect to make 
two proximo-occlusal fillings instead; however, they may be so inter- 
locked as to represent the same outline form as the mesio-occluso- 
distal filling. 

The proximal cavities of the anterior teeth present some difficulties 
owing to the fact that we have less surrounding wall. (Figs. 212 to 214.) 
For illustrative purposes take the mesial of a central incisor. The 
gingival point angles are filled first, and the axio-gingival line angle is 
covered as described in the preceding case. The surface of gold 
should then be built toward the incisal, preserving an angle of about 
45 degrees, and it should be borne in mind constantly that the lingual 
portion is to be kept in advance. The incisal retention form is filled 



23<5 



FILLING MATERIALS. 



as soon as the gold can be attached from it to the main portion, and the 
body of gold thus tied and strengthened. 

Great care should be taken in covering the margin both lingually 
and labially at the proper time, and also in sufficiently contouring the 
lingual. In cavities involving the angle without a step, the building 
of the gold is continued to proper contour. (See Figs. 215 and 216.) 
Pluggers used for the gingival retention form are 187, 188, and 189; 
for the body of the filling, 195, 196, and 197; for the incisal retention 
at times necessary to add, 190. 

When the incisal edge is involved, and the step preparation has 
been made, the filling of the proximal portion is proceeded with pre- 
( isely as described until the step is reached. The retention form in the 







Fig. 217. 



Fig. 218. 



Fig. 219. 



Fig. 220. 



Fig. 221. 



Fig. 217. — Mesio-distal plane. Showing disto-pulpal angle filled. 

Fig. 218. — Same as preceding, further progress. 

Fig. 219. — Same as Fig. 218. Gold building completed. 

Fig. 220. — Upper second bicuspid. Axio-bucco-lingual plane. Showing the three non- 
cohesive cylinders of gold in place. 

Fig. 221. — The same tooth as that in Fig. 220. Axio-mesio-distal plane, showing 
partially condensed mass of non-cohesive gold projecting over gingival cavo-surface angle 



incisal part is then filled from the disto-pulpal angle, and the gold 
built down so that its surface will present an angle, of 45 degrees with 
the pulpal wall, and on towards the proximal portion, covering the in- 
cisal edge. Lastly, the union of the two portions is completed, and 
carried out to contour. The force exerted here should always be so 
as to drive the whole filling more tightly into its retention and resistance 
forms. (Figs. 217 to 219.) 

In the filling of a mesio-inciso-distal cavity in the six anterior teeth, 
the proximal portions are filled as before ; in filling the incisal portion, 
however, the center should proceed faster than the angles, and it is 
also best to build one angle out to contour first, remove the separator, 
and proceed with the remaining one exactly as before. 

A great deal has been said about the percentage of failures of 
adaptation to the gingival wall in bicuspids and molars when using 
cohesive gold for the entire cavity, although on this point statistical 
figures may vary quite as widely as do opinions of what legitimately 



GOLD. 237 

may constitute such figures. Some of the best operators prefer to 
use a certain amount of non-cohesive gold in the gingival part of the 
cavity. The advantage is, besides better adaptation, a saving of time 
which is, of course, a vastly important factor in the economics of the 
question. 

The non-cohesive gold should not fill the whole of the retention 




Fig. 222. — Labial view of six anterior teeth. Showing contour and contact. 

form. The usual method of procedure is to place one cylinder in the 
axio-linguo-gingival point angle, another in the axio-bucco-gingival, 
with a third between, and partially force them together with the plug- 
gers 192 and 193. The cylinders used should be about twice as long 
as the gingival wall is wide mesio-distally to allow for after-conden- 
sation. (See Figs. 220 and 221.) The cohesive gold is now forced 
into the non-cohesive, using an assistant plugger, while locking the 
gold from the lingual to the buccal wall. Thus the cohesive gold 





Fig. 223. Fig. 224. 

Fig. 223. — Buccal view of bicuspids and molars. Showing contour and contact. 

Fig. 224. — Occlusal view of upper bicuspid and molar. Showing contour and contact. 



really forms the fourth surrounding wall for the non-cohesive. Thence 
the filling is proceeded with as in the operation already described 
where cohesive gold was used for the entire cavity. 

The final condensation of the non-cohesive gold takes place from 
the surface, by means of large parallelogram pluggers (see Figs. 197, 
198, 199, and 200, the last three for distal surfaces). 

In finishing, it is assumed that the cavity has been overfilled to 
allow for trimming away of enough gold to leave a perfectly smooth 
surface, and still have proper contour. The instruments and appli- 



FILLING MATERIALS. 




Fig. 225. — Occlusal view of 
lower bicuspid and molar. Show- 
ing contour and contact. 



*-* 



ances for this purpose are many. Of them, the following are indispens- 
ible: A plentiful supply of corundum stones in various sizes and 
grits, sandpaper discs and strips, the Wilson saw frame (Fig. 226) 
and saws cut down to a thread-like thinness, Dr. G. V. Black's trim- 
ming knives (Figs. 227, 228, 229) and Dr. 
E. K. Wedelstaedt's gold files. (See illus- 
tration, Fig. 230.) 

Generally the first cutting is done with 
the aid of corundum stones or sandpaper 
discs and strips, depending upon locality, 
and, in proximal positions, the saw is an 
adjunct of great importance. Thereafter, the steel instruments, chisels 
and excavator for inaccessible places in occlusal fillings, trimming 
knives and files, and, for the final smoothing, cuttle-fish discs, pumice 
stone, whiting, or rouge, used with suitable appliances. 

The chief watchword in this part of the work should be: Lacerate 
the tissues as little as possible; reproduce natural form plus the needed 
contour and contact point (Figs. 222 to 225); obtain as 
smooth a surface as possible so that an explorer will pass 
from filling to tooth tissue without catching. Always cut 
from the gold to the tooth tissue as far as possible. As to 
the use of the knives, only thin shavings should be cut, and 
the force should be directed so as not to disturb the filling. 

Occlusal fillings are first ground down with corundum 
stones and water, starting with reasonably coarse grits, and 
finishing with finer ones. A variety of shapes is necessary 
in order to reach well into grooves and variations in sur- 
faces. A good polish can be obtained by using fine, wet 
pumice stone powder applied with wooden wheels or points, 
rubber discs, or moosehide wheels. This may be followed 
with whiting and even rouge for a very high degree of polish. 
In buccal, labial, and lingual fillings, the use of discs 
should be substituted for part of the corundum work; but 
both these materials are very liable to cut too much into 
the filling. The pointed fissure burs can be used over the 
gingival margin. The Black trimming knives and Wedel- 
staedt files are all of use here. The polishing is done as above 
indicated. 

In the proximo-occlusal fillings the saw is passed under the gin- 
gival overhang, and should be first drawn carefully toward the contact 
point, and with it as much as possible of the remaining overhang 



Fig. 226. 



GOLD. 



239 



u 



should be removed, or as much as the limitation of movement will 
allow. The trimming knives can now be used, and should be followed 
by the files, with some care to guard against too much 
cutting; the needed contour and symmetry of shape must 22 8 227 229 
always be remembered. 

Further smoothing is done with sandpaper discs and ^ 
strips, followed by the usual polishing process. It is 
often necessary to carry the polishing powders on linen A 
tape over the proximal portion, in order to finish thor- 
oughly. 

In proximal fillings in the six anterior teeth, the first 
cutting is usually done with sandpaper discs and strips, 
although the corundum stones are material aids on both labial 
and lingual surfaces, especially the latter. It may also be neces- 
sary to use the saw, knives and files for the purpose of removing 
the gingival overhang; but they are perhaps not needed so much 
here as in the posterior teeth. Polishing is done with cuttle-fish 
discs and strips, and with the powders. The incisal angle and 
edge, when involved in a filling, demand a greater use of corun- 
dum stones and sandpaper discs. 

Considered as a stopping, nothing as yet has quite taken the 
place of gold, although it cannot be said to apply perfectly to all 

t\ VB 1 i\ \ 1 cases - A ^ un knowledge of its properties, 
behavior, and working qualities, is the first 
essential. With skillful instrumentation 
and bulldog persistance, one ought to be 
able to conquer the art of making nearly 
perfect gold fillings in a comparatively short 
time, say in from five to ten years. 

Reference has been made to the dis- 
covery of the cohesive property of gold as 
marking an epoch in the history of tooth- 
filling. Another epoch may be said to have been ushered in by 
the scientific and artistic work of Dr. G. V. Black. The world- 
wide influence exerted by this great worker may be noted in 
papers, reports of clinics, etc., published in the various journals 
by members of the G. V. Black Club (Inc.) of St. Paul. This 
organization has done much to simplify gold filling, and, in 
general, not only through its home meetings, but in state, 
national, and international gatherings, has done much to further the 
progress of operative dentistry. 




Fig. 230.— Dr. E. K. 
Wedelstaedt's gold files. 



240 FILLING MATERIALS. 



AMALGAM. 



Owing to the plasticity conferred upon an alloy of one or more 
metals with mercury, amalgam is usually spoken of among the plastic 
filling materials. What takes place in the union is the lowering of 
the fusing point of the alloyed metals by introducing mercury, a plastic 
stage thus ensuing before crystallization is complete. This plasticity 
and subsequent crystalization — both interesting phenomena — led to its 
introduction as a filling material. 

The study of amalgam is somewhat complex because we have to 
deal with an alloy of certain metals not always constant in physical 
properties out of the mouth, and liable to still greater modification 
after introduced into the cavity as an amalgam. For various appli- 
cations in the arts, metals are alloyed to gain specific ends not obtain- 
able by any one of them alone: to increase hardness, strength, tough- 
ness, elasticity, and resistance to corrosion; to lower the fusing point; 
to modify color, etc. 

Alloy making and application were known to the ancients, although 
they did not always produce what they intended to, nor did they know 
very much about the separate elements. Alloy for amalgam fillings 
was introduced in the first quarter of the last century. Things were 
done on a more or less empirical basis until the impetus of scientific 
method altered matters. Although formulas may not have changed 
markedly, there has been undoubted improvement as to certainty of 
procedures and results. It was the general lack of applied science 
which made it so difficult for amalgam to take its present place of use- 
fulness, and w r e owe a debt of gratitude to all the zealous workers who 
have combined to give it that place. The early prejudice against it 
was due to its non-scientific composition and use. It is, perhaps, 
needless to say that amalgam has been criminally abused in the past, 
and that the better conditions which might naturally be expected from 
scientific workers have not been commensurate with their efforts. 
Its plasticity readily betrays operators into unwarranted speed — a fact 
which is only too soon recognized by the charlatan class. 

Some properties of amalgam should be noted. Its color is grayish 
white. It is generally spoken of as brittle, although under certain 
conditions it manifests a degree of malleability known as "flow." 
It is harder than silver, but not very tenacious. Gases are condensed 
upon its surface to a larger degree than with gold. As to conductivity, 
all alloys have less of this property than do the simple metals. These 
properties are modified, first, according to the number and quantity 



AMALGAM. 241 

of the various metals added; and, second, according to the mode of 
making. 

As to the manner in which amalgam fulfills the requirements of a 
filling material: It may be said to be practically indestructible in 
the mouth. Chemical action of any kind is always more energetic in 
alloys, hence amalgam unites easily with oxygen and sulphur. In 
adaptation to cavity walls, it is nearly as good as gold. The change in 
form in amalgam, due to contraction and expansion, so noted in the 
past, has been reduced by modern science to the minimum. It with- 
stands attrition well, and, in general, the forces of mastication are not 
so manifest upon well-made fillings of this material as upon those of 
gold. Its color is one serious drawback. Its conductivity is low, far 
lower than that of gold. As to ease of manipulation, this property 
increases in proportion to the amount of mercury introduced in the 
alloy; but the operator must choose between this advantage and the 
superior one of firmness, for, if the latter be the desideratum, it must 
be had at the expense of the former. In susceptibility to polish, it 
fulfills the demand. 

The properties of amalgam decide its application, to a large extent; 
for instance : its color limits its use to the posterior teeth, or where it is 
little noticed; the possibility of easy manipulation often determines 
its use in cavities inaccessible to gold. So then, generally speaking, 
it can be used in the bicuspids and molars, especially in cases where 
more nearly perfect results can be obtained than by the use of gold. 
However, if exposed to view to any extent, it is contra-indicated. We 
may say that so far as it is peculiarly adapted to such selected cases, 
it becomes the ideal material. 

If success is to be obtained in amalgam work, the following points 
must be carefully considered: The individual metals used; the purity 
and the proportion of the metals; the manner of production; and the 
manipulative procedure. The study of the chemical and physical 
constants of the metals is imperative. As to the behavior of metals 
toward one another in alloys, it may be said that mixtures are not 
merely mechanical. They are in the nature either of a solution of one 
metal in another, or of a chemical combination. A chemical combina- 
tion may be a pure one, or it may provide an excess of one of the metals 
in which latter case the excess is mingled mechanically w T ith the mechan- 
ically combined constituents. Proportion, temperature, etc., of course 
determine the final manner or manners of the combination. 

There is no hard and fast rule regarding the reciprocal action of 
metals in alloys. Some metals alloy easily in any proportions; some 

t6 



242 FILLING MATERIALS. 

less easily and in only set proportions; and again others alloy with 
extreme difficulty under any conditions. As a rule, metals of similar 
chemical nature have greater affinity as alloys than those which differ. 

Mention should be made of the fact that only chemically pure 
metals ought to be employed. Otherwise, unaccountable variation 
will manifest itself. 

The proportion of metals is of considerable moment. Experiments 
have shown that like quantities of metals alloyed alike produce cer- 
tain results. Furthermore, the addition of a very minute quantity of 
some metals is capable of causing great modification in the properties 
of the resultant alloy. The manner of production is of tremendous 
importance, for instance: 

If metals be heated to a temperature beyond the fusing-point, a 
different atomic grouping may occasionally result. The length of 
time they are kept in the fluid state, the mixing process, the various 
methods of cooling and casting, may noticeably modify an alloy. In 
some cases when cooled slowly, they will separate into several alloys of 
differing compositions; that is, the alloys with a higher fusing-point 
solidify first. This is spoken of as liquation. At the same time spe- 
cific gravity may manifest itself so that the lightest alloys, if solidified 
last, may be uppermost. If liquation take place, there will be not only 
variation in composition, but also, to a marked degree, in the properties. 
Liquation should, therefore, bp prevented as far as possible wherever 
constancy of properties ought to prevail. This can in the main be 
accomplished by rapid cooling. 

It is clear then, that much depends upon the manner of production. 
The foregoing remarks may be made more clear by a description of the 
process of making dental amalgam alloy: 

Take the formula 60 per cent silver, 35 per cent tin, 4 per cent cop- 
per, 1 per cent zinc. To make 10 oz. we shall need 6 oz. silver, 3J oz. 
tin, 8 dwts. copper, 2 dwts. zinc. Zinc is added in the combination of 
brass, because free it is easily volatilized and oxidized. The brass, 
however, should be of known proportions, say 75 per cent copper 
and 25 per cent zinc (a constant alloy). The weight will then be 2 
dwts. copper and 8 dwts. brass. The brass, copper, and silver are 
fused in a plumbago crucible first. The tin is fused in a separate 
ladle, and added as soon as the first three are in fluid condition. Fusing 
all the metals at once has been tried, and analysis and experiment show 
greater variation. Some stirring is necessary until the pouring out 
begins. A quarter inch steel "mold about four inches wide cools the 
alloys fast enough. One out of every thousand melts, as above, were 



AMALGAN. 243 

subjected to analysis by Prof. C. J. Bell in the chemical laboratory of 
the University of Minnesota. Five sections of the bar were made, 
and the percentage of each metal was very nearly the same in all, and 
according to formula. 

If thicker castings be made, liquation is very liable to take place. 
The bar can be reduced by means of a twelve-inch bastard file, and 
strained through a brass wire mesh. Iron filings from file and bench 
vise may be removed by passing the magnet through for several min- 
utes, and it is then aged by subjecting it to the temperature of boiling 
water for about twenty minutes; the mass is placed in a beaker, and 
introduced into a pot of boiling water. 

The silver is added for its hardening and settling qualities; it also 
causes expansion. Tin is added chiefly to counteract the expansion 
caused by the silver, and to retard the setting, Copper increases 
hardness and strength, and has some effect upon color. Zinc heightens 
the color, and somewhat hastens the setting. 

The percentages of dental amalgam alloys haye been determined 
by experiment. For a detailed study of them the reader is referred to 



Fig. 231. 

the scientific investigations of Dr. G. V. Black {Dental Cosmos, Vol. 
28, and elsewhere). 

Dental amalgam alloys are classified as binary, ternary, etc., accord- 
ing to the number of metals added. 

With amalgam the most vital point for consideration is the manipu- 
lative procedure. Not only is the percentage of mercury to be reck- 
oned with, but also its incorporation, the compression of the mass, 
trimming and finish, are all elements that figure prominently in the 
results. One reason that this material has not reached a higher plane 
generally is a lack of sufficient study and attention to minutiae and 
detail in the technique of insertion. This deficiency should be more 
widely acknowledged and repaired. 

It has been the writer's privilege to observe several hundred amal- 
gam operations made by Dr. F. H. Orton, of St. Paul, during the past 
twelve years. The results have been uniform, and as nearly perfect 
as are ever seen. His method of procedure is incorporated in the fol- 
lowing description of filling a cavity with amalgam: 

The cavity is prepared as for gold, with this difference, that the 



-44 



FILLING MATERIALS. 



enamel bevel should be somewhat longer. All cavities must be simple; 
it not so in the first place, they must be made so by adjusting a matrix 
to replace the missing wall. The matrix should be unyielding and fit 
clo 




Fig. 232. — Black's hand 
pressure amalgam instruments. 



sely to the tooth-surface. The amalgam is prepared by placing 
the mercury in the palm of the hand, and 
gradually adding the alloy until affinities 
are practically satisfied. The hand should 
be perfectly clean and dry. The incorpora- 
tion of the ingredients is accomplished by 
rubbing with a glass pestle. (See Fig. 231.) 
Both judgment and -skill are necessarv to 
obtain the proper mix; a certain crepitus is 
noticed when the mass is about ready, and 
some experience will enable one to know 
when this point is reached. It should be an object to have as 
little surplus mercury as possible when the mixing is finished; there- 
fore it is forced out in chamois skin or muslin with heavy pliers so 
much so that the mass should resemble a hard, flat cake which fractures 
sharply. In packing the amalgam the object is density and complete 
union of all the particles. As it is some- 
what plastic, the plugging points should 
be as large as the cavity will permit, and 
with serrated surfaces (see Figs. 232, 233, 
and 234). Hand pressure as ordinarily 
understood is not sufficient; hence the aid 
of the mallet comes in, using bayonet 
shanks as illustrated. It will be found 
that it requires a rather heavy blow from 
the mallet to compress the amalgam, and 
that the blows must be repeated until the 
mercury appears under the plugger point. 

is then removed by the aid of gold foil, the two metals having a 
marked affinity for each other. A cylinder of gold foil is placed 
upon the surface, covered with spunk, pressed down and removed. 
More amalgam is then added, and the process is repeated until 
the cavity is overfull. Importance should be attached to the 
removal of the surplus mercury whenever it appears; if allowed to 
remain, it weakens the mass. If care is taken, the amalgam will be 
sufficiently crystallized to admit of trimming immediately. For occlu- 
sal surfaces large spoon excavators should be used, and for proximal, 
trimming knives and coarse cuttle-fish strips and discs. Fillings in 



M 



Irl 




Fig. 233. — Black's 
amalgam instruments 
with bayonet shanks for 
mallet use. 

This surplus mercury 



TIN. 



245 



other positions present few difficulties in trimming. The same instru- 
ments with some additional chisels or excavators for special inequali- 
ties will be found all-sufficient. 

It is best to postpone for a day the final polishing. First corundum 
stones, and then powders, are used, as in the polishing of gold fillings. 
Since in time these fillings undergo a slight change in form, , „ 

it may be necessary to refinish afterwards, as occasion 
demands. 

The time required to make a good amalgam filling is 
nearly that required for gold; therefore were it not for the 
fact that in certain cases it excels all other materials, 
there would be no economy in its use. Many large 
cavities may be filled with amalgam when the malleted 
gold filling would be entirely out of the question. Restor- 
ations of considerable magnitude are often made, whereby 
teeth are rendered useful for a number of years. 

Although amalgam is not proclaimed as the acme of 
desirability, it occupies a very high place as a tooth 
saver, and it is we'll worth effort and energy to increase 
our knowledge concerning it. There is yet a wide field 
open to the investigator in alloy making and application. 
With what has already been achieved, however, the 
student can and should thoroughly acquaint himself, and 
thus conserve time by eliminating the errors and profiting 
by the valuable discoveries of the past. 



TIN. 



Fig. 234.— 
Owre's right 
and left amal- 
gam instru- 
ments for 
use against 
matrices at 
junction o f 
same with 
c a v o-surface 
angle. 



For various reasons tin is still used by some dentists, 
and the ability to insert a tin filling is a test in some 
official examinations. Hence this material should be studied. 

In color it is white with a tinge of yellowish-blue. When pure it 
has a bright, metallic luster, and although in normal air it does not 
easily tarnish, it readily occludes gases. It is fifth in the order of mal- 
leability, foil xoV 0" °f an mcn tmn being obtainable by beating. It 
is classified with the soft metals, and is also of a low grade of tenacity, 
being tenth in the scale at 2.1 tons per square inch. Its specific gravity 
is 7.3. It is weldable in the cold state if perfectly pure, and purity 
generally implies fresh-cut surfaces. When w r eldability has been in- 
terfered with by exposure to air, it cannot be restored by annealing. 
As to conductivity, tin ranks low: for heat, 154; for electricity, 114. 

Tin has been used as a filling material for a century or more; but 



240 FILLING MATERIALS. 

it only partially fills the requirements of this purpose. It oxidizes 
readily in the mouth, is easily adapted to cavity walls, and undergoes 
no change in form unless subjected to wear, and, when so, the mallea- 
bility and softness markedly manifest themselves. Its color is objec- 
tionable. So far as conductivity is concerned, it is low enough to be of 
value. The manipulation is very like much that of gold. It receives 
a fairlv good polish. Occasional reference has been made to its 
therapeutic value, when used as a filling, as a preventative of caries, 
etc. This seems highly improbable, excepting insofar as it replaces 
the carious area, as does any other filling material. 

Tin has been recommended for cavities which are not exposed to 
wear and tear, and is practically limited to simple smooth-surface cav- 
ities not exposed to view or wear. It may have some application to 
cases of young children, owing to its rather easy manipulation. 

It is prepared for the dentist in several forms, but the foil is chiefly 
used, between Nos. 3 and 10. But, as this soon loses the property of 
cohesiveness, the dentist had better prepare the shavings of tin himself, 
when wanted, by casting an ingot upon a polishing mandrel, attaching 
to lathe, and, with a sharp tool, cutting as fine shavings as desired 
for the case in hand. 

Its insertion is exactly according to the method pursued with gold, 
the only difference being that the plugger points may be more deeply 
serrated. The finishing, also, is the same as in the case of gold. 

Since science has aided us in establishing the status of things, it 
would seem as if the future of the tin filling were somewhat dubious. 
Personal opinion need not obtrude itself here, for speculation belongs 
only to the field of theory. 

CEMENT. 

Among the applied arts, cement, in its various forms, has been 
in use for centuries. Its introduction to dentistry did not occur until 
about fifty years ago. Largely owing to lack of science, it has had a 
degree of difficulty in establishing itself as a filling material, as also had 
amalgam. For that matter, its status quo, all told, is still somewhat 
doubtful. Nevertheless, it serves many important and useful pur- 
poses — so much so that we have come to regard it as indispensable. 

Of the three kinds of cement to be considered, *. e., the oxychloride 
of zinc, the oxyphosphate of zinc, and the oxyphosphate of copper, 
the first is at present little used. The use of zinc oxychloride as "a 
stopping of hollow teeth'' was first suggested because of its plasticity 
when freshly mixed, its subsequent harden irg, ard its apparent in 



CEMENT. 247 

dissolubility. Its shortcomings were soon discovered, and various 
modifications of the powder and liquid were tried for the purpose of 
enhancing its qualities, but to no avail. 

The oxyphosphate of zinc, introduced some years later than the 
oxychloride, gave promise of greater things. It has largely taken 
the place of the oxychloride, except for some special purposes to be 
noted. Upon it our main reliance was placed until quite recently 
— in 1891 — when Dr. W. V-B. Ames, of Chicago, brought out the 
oxyphosphate of copper. 

Some general properties of all cements should be noted: Plas- 
ticity, facility of setting, granular structure, low strength, porosity, 
marked solubility, and low conductivity. As to color, the oxychloride 
is nearest white, the zinc oxyphosphate has various hues, while the 
copper oxyphosphate is the blackest of black. The properties vary 
a great deal, according to composition and modes of mixing, especially 
those of density, setting, porosity, permeability, disintegration, etc. 

To a certain extent all cements possess the essential qualifications 
for a filling. But they are not indestructible in the fluids of the mouth, 
especially under the free margins of the gum. The oxychloride is 
the worse in this respect. Their adhesiveness to cavity walls is of 
great value. Some cements undergo change in form, particularly 
through contraction. None resist attrition well, although oxyphosphate 
of zinc and copper wear much better than the zinc oxychloride. As 
to colors, highly artistic results may be obtained with some of them, 
but the black of copper oxyphosphate limits the application of it to 
unexposed places. Cements are practically non-conductors of heat, 
and are often indicated for this reason. As to ease of manipulation, 
they are undoubtedly first of all materials. They are incapable of 
receiving or maintaining a very high polish; although when first finished 
the surface may be fairly smooth, with wear it soon becomes granular. 
Some of them are, in general, less irritating to tooth tissue than metal- 
lic fillings, and this is one of the most important considerations. Oxy- 
phosphate of copper has been found to be extremely bland when used 
near the pulp, or even in contact with gum tissue. In regard to the 
porous structure, this is capable of some reduction through modifi- 
cation of constituents. 

Turning to indications for the use of cement: At present the oxy- 
chloride is not used to any extent as a filling for the entire cavity, 
because of its speedy disintegration, and the irritating character of the 
chloride. Many authorities agree in indorsing it as a cavity lining 
because of its white color, its density, and therapeutic value. It should 



248 FILLING MATERIALS. 

not be used too close to the pulp, because of the irritation likely to 
result . but it may be used to advantage in pulpless teeth for the larger 
portions of the canals and to fill the pulp chamber. 

We are considering then, practically, only oxyphosphates of zinc 
and copper. Fillings prepared from these materials are spoken of as 
temporary, it being implied that they will be replaced sooner or later 
by more nearly permanent ones. While this is correct, we must not 
lose sight of the fact that some teeth will never be filled with anything 
more permanent, i. e., cement seems peculiarly and preeminently to 
lend itself to the preservation of certain teeth. It is, par excellence, 
the material for use in all cases where for any reason no adequate 
cavity preparation can be made for the so-called permanent 
fillings. 

It is also indicated in some other cases: those of very old people, 
and those of younger people in whose teeth caries is acute. In the 
latter case it is introduced as a temporary filling in the true sense of 
the term, in extending the usefulness of frail or deciduous teeth. 

In discussing the preparation of cements, we are confronted with 
the large and insurmountable trade-secret proposition. The mere 
names indicate some of the chief ingredients; but of the various methods 
of production, the modifying agents used, etc., we have very little 
data. As it comes to the operator's hand, a cement is made up of a 
powder and a liquid. The powder of the oxychloride of zinc is com- 
posed chiefly of oxide of zinc, calcium oxide being often added to 
hasten setting, and other ingredients to obtain certain other proper- 
ties, as silicate of aluminum, magnesium oxide, sodium borate, silex, 
powdered glass, etc. 

The oxyphosphate of zinc is principally composed of glacial phos- 
phoric' acid and zinc oxide, to which are added, for the purpose of in- 
creasing hardness and lessening solubility, several foreign ingredients, 
e. g., sodium phosphate gives the liquid a glassy consistence in hand- 
ling. A chemical analysis of cements shows the following impurities:* 
arsenic, antimony, lithium phosphate, cadmium sulphide, carbon, 
fluorhydric acid, nitric acid, sodium carbonate, powdered glass, silex 
and water glass, sodium borate, magnesium oxide, magnesium nitrate, 
sodium phosphate, silicate of alumina, phosphate of alumina. The 
fineness of the powder varies not only with different makes, but occa- 
sionally with different lots put out by the same maker. The finer it is, 
the quicker it sets. 

The oxyphosphate of copper is composed of the same liquid as 

*Dr. J. E. Hinkins, Dental Cosmos, Vol. xliii, p. 591 



GUTTA-PERCHA. 249 

the foregoing, and cupric oxide, with or without addition of other 
metallic oxides. 

The preparation of cements for filling cavities is not very difficult, 
but some care is necessary. The phosphoric acid has a tendency to 
crystallize. To lessen this, Dr. Ames recommends keeping it in a tele- 
scoping glass cap bottle, instead of one with the cork fitting within 
the neck. The prime requisite in mixing is thorough spatulation. 
Powder should be added to the liquid in only a small mass at a time, 
and before use the mixture should attain a putty-like consistency. 

In the case of oxyphosphate of copper, a creamy mix seems to 
give best results. It should be needless to say that the glass slab, 
spatula, and other instruments used in handling cements must be 
scrupulously clean and well polished. 

Cements vary somewhat in their working qualities. Hence, good 
results can be made sure of only by more or less experience. 

The cavity preparation for cement fillings is simplicity itself, since 
the adhesiveness of the material may be very largely depended upon 
for securing the filling to the cavity walls. The complete removal of 
caries should in every case be insisted upon, however. In inserting 
the material, one must remember to overfill the cavity, and to use as 
nearly as possible even pressure from all points. For this work broad, 
flat burnishers are usually employed. These should first be rubbed 
upon an oil-pad to prevent the cement from adhering to them. The 
filling should then be left thoroughly to crystallize before trimming, 
which process is accomplished with chisels, trimming knives, and occa 
sionally burs. A fairly smooth surface may be had by the aid of fine 
sandpaper discs or strips. 

The cement operation, with proper care, may be made a very suc- 
cessful one. That it has fallen in estimation somewhat, is due largely 
to the fact that the apparent ease of cavity preparation and of manip- 
ulation lend themselves to charlatanism. Used by skillful hands 
in the proper places, cement has, in spite of its lack of durability, a 
valid claim to a position among filling materials. 

GUTTA-PERCHA. 

The name gutta percha is applied to the inspissated juice of various 
plants belonging to the natural order Sapotacea. The term is of 
Malayan origin, gutta signifying gum, and percha, the species of tree 
from which the gum is derived. It is native in the Malay Peninsula, 
and although its use has long been known in the Orient, even back 
into antiquity, it was not introduced into the western world until earlv 



250 FILLING MATERIALS. 

in the Last century, when its great possibilities in the realm of manufac- 
ture were recognized. It was taken up by dentists about 1850, and, 
according to Dr. J. Foster Flagg, it was then suggested as a temporary 
stopping for frail teeth, and was recommended for its ease of manip- 
ulation, its non-irritating and non-conducting character, its insolubil- 
ity in the fluids of the mouth, and its reasonable resistance to attrition. 
He further asserts that w T ith it he could make better fillings in certain 
places than with gold. Various modifications of it were introduced 
better to meet the dentist's requirements. But the difficulties attend- 
ing its manipulation, its non-resistance to attrition, and the gradual 
gain of cement, have lessened its use. Lastly, the introduction of 
copper oxyphosphate has almost crowded it out as a filling for the entire 
cavity. 

The properties of gutta-percha are its decidedly low conductivity, 
its blandness, or non-irritating character, its agreeable color, and its 
insolubility. It lacks hardness, even when foreign substances are 
introduced to increase this property. Its contraction on cooling is 
also an objection, as is also its more or less porous structure. It is 
insoluble in the fluids of the mouth; it can be reasonably well 
adapted to cavity walls; it changes in form, notably by contraction; it 
does not resist attrition; its color is not objectionable and is easily 
modified; it is the best material we have for non-conductivity; it is not 
so easy of manipulation as cement; it takes no polish at all. 

Gutta-percha is indicated wherever a perfect non-conductor 
is needed; but as it cannot be used in any place w^here it will be sub- 
jected to attrition, it is decidedly limited in its application. It is 
especially applicable to the filling of small pulp canals in pulpless 
teeth. 

Commercial gutta-percha is prepared by boiling and purifying in 
a number of ways. When nearly pure, it is of a grayish-white color 
which can be modified as desired. For dental uses the pink base 
plate gutta-percha seems to be best. It is colored by means of sulphide 
of mercury. 

Its successful use involves considerable skill. It must be heated 
until soft enough to permit of its being adapted to the cavity walls. 
In this process it must never come in contact with the open flame. 
Various devices are employed for heating, such as porcelain trays to 
be held over the flame, or sand-bath. If overheated it is ruined. 
Ordinarily the instruments used are flat burnishers w T hich should be 
warmed and oiled. The cavity should have some retention form, 
and it is also w T ell to coat the cavity walls with oil of cajeput or eucalyp- 



COMBINATION FILLINGS. 25 I 

tus. Dr. Black remarks that these oils take strongly to cavity walls, 
and also slightly dissolve the surface of the gutta-percha, hence their 
value. 

The material is packed piecemeal into the cavity, or en masse, 
care being taken to insure thorough adaptation. One should guard 
against obtaining too much surplus, for gutta-percha does not lend 
itself so well to trimming aid finishing as do other materials, although 
surplus can always be removed by the aid of a warmed burnisher. 
Or, when it has sufficiently hardened, it can be trimmed with thin, 
sharp trimming knives, always cutting from center to periphery. 

That gutta-percha has possibilities is undoubtedly true. It will 
in all probability be continued in use for some time to come. But, 
if personal opinion were not out of place, we might close this discus- 
sion by observing that the attitude of the dental world seems to the 
present w r riter to be that gutta-percha as a filling material for the 
entire cavity, all things considered, is distinctly altered since the virtues 
of copper oxyphosphate have been fully made known. 

COMBINATION FILLINGS. 

The term "combination fillings" has been made acceptable by 
usage, although it is not in all cases strictly accurate. 

The fact that no one material possesses all the virtues desired, 
together w T ith other reasons, as, for instance, the greater ease with which 
particular parts of the same cavity lend themselves to particular ma- 
terials, have led to frequent indication of more than one material for 
the filling of the same cavity. A few of these will be taken up for 
discussion, although it must be remembered that endless combinations 
may be made, according to the necessities of the case, and the ingenuity 
of the operator. 

Platinum and gold are used together, chiefly for resulting color 
and density. Platinum is bluish silver-white in color. Its specific 
gravity is 21.46. The color of the combination varies between light 
and dark gray, depending upon the quantity of platinum used. This 
platinum-gold combiration withstands attrition better than gold 
alone. For esthetic reasons it is indicated in cases when patients 
are of dark complexion. It is also desirable when more density is 
sought than gold alone can supply. 

Platinum-gold for filling is used in the forms of folds of both metals, 
of platinized gold folds, and of platinum and gold foil. It is best not 
to use it for the entire cavity, a surface of this composition being quite 
sufficient. Generally speaking it is manipulated in the same manner 



252 FILLING MATERIALS. 

as gold alone; but a little more care is called for in annealing and con- 
densing. That is, it is easily overannealed, and a small condensing- 
area plugger point should be used and moved only its own width each 
time, thus insuring thorough condensation. It may be worth noting 
that this serviceable combination of platinum and gold has of late been 
replaced largely by the porcelain and gold inlays — the porcelain inlays 
chiefly in the anterior teeth, and the gold in many cases where great 
surface is to be restored for the purpose of resisting attrition. 

The properties of gold and tin have already been considered. 
Tin has been used to fill part of a cavity, the finishing of which is done 
with gold. Tin was largely applied in proximal cavities to cover the 
gingival wall, in the same manner as non-cohesive gold; but this opera- 
tion is practically discontinued, owing to what seems to have been a 
dissolution of the tin. 

One method of preparing tin in this connection is to take it in sheet 
form, superimpose it upon a sheet of gold, cut to desired widths, and 
make into cylinders, as described under " Gold." A few operators 
use this combination in occlusal cavities in deciduous teeth, and in 
the gingival third of bicuspids and molars in the adult teeth to a limited 
extent. 

It is handled in every respect like non-cohesive gold. It is undoubt- 
edly true that this goldrtin filling may conserve certain teeth; but re- 
cent investigation has led to the improvement of amalgam and its 
consequent preferment over the gold-tin combination in many cases 
where the latter might formerly have served. Also, in the gingival 
portion of cavities there seems to be an increase in the use of non-cohe- 
sive gold alone; so that, on the whole, the outlook for this combination 
is not the most encouraging. 

The gold and amalgam combination is, at times, of great value, 
amalgam being used either to fill inaccessible parts of cavities, as 
below the gingival line, or merely to lessen the bulk of gold in very 
large cavities. In complex cavities it is often admissible to fill, for 
instance, a disto-occlusal cavity with amalgam, and the mesio-occlusal 
with gold, making a step into the amalgam. 

Gold and Cement. — Besides using the cement for its inherent vir- 
tues, it is also employed to lessen the bulk of gold in large cavities and 
in pulpless teeth. 

The amalgam and cement combination is used similarly to the fore- 
going. Cement is also used in amalgam operations to strengthen 
weak walls, in which case it practically becomes a cavity lining. 
Frail teeth can often be thus preserved for a remarkably long period. 



COMBINATION FILLINGS. 253 

Cement and Gutta-percha. — Owing to the fact that gutta-percha is 
not soluble in the fluids of the mouth, it can be used in the gingival 
portion of proximo-occlusal cavities, cement being employed, since it 
is somewhat denser, for finishing the rest of the cavity. In general, 
it is not advisable to let metallic fillings rest upon gutta-percha, owing 
to lack of firmness in the latter; but a cement intervening will afford 
the proper support. 

It is difficult, if not impossible, to acquire from a text-book the art 
of filling teeth, be the text ever so explanatory and complete in detail. 
Theory must be supplemented by practice. To strike an even balance 
in this respect is a task of some proportions. In filling teeth, we imi- 
tate the work of others. Possibly we perfect a detail here and there, 
make a new discovery, or improve a method. The imitative aspect 
of the profession predominates, however. But this should not dis- 
courage us. All told, the world we live in is an imitative one, the 
absolutely new things discovered from decade to decade being very 
few indeed. 

Although his technique may have been revolutionized, the art of 
the sculptor has not changed since Phidias wrought upon the Parthenon 
or that unknown and remoter hand carved the Sphinx's features in the 
Valley of the Nile. The bases of the arts do not shift with the years; 
that which is of permanent value rests upon solid foundations like 
those of the Sphinx or the Pyramids amid their waste of unsteady soil. 
That which is good abides, and our own virtues may be measured ac- 
cording to the degree in which we show ourselves appreciative of the 
virtues of those who have laid our professional foundations. 

We might say that we have now reached a certain stage of perfec- 
tion in the preparation of cavities in teeth, and also in filling them with 
gold and other materials. Such advancement as has been made should 
be rigidly maintained. We should not, however, be content to rest upon 
achievements. We must keep the mind receptive to possibilities, and 
the hand pliant and supple to slowly evolved technical inventions. 

We have often seen and heard emphatic statements from operators 
to the effect that gold is the ideal and only filling in all cases, and that 
they use nothing else. Such statements are misleading to beginners 
who many times take them too seriously. Experience soon teaches 
that one cannot successfully adapt gold to all cavities. But the ques- 
tion, "what is the best filling?", implying that one material for all 
cases is possible, will often be heard from both scientific and unscien- 
tific people. Of course, the question cannot be answered as it is put. 
The whole of the foregoing chapter demonstrates this. An attempt 



254 FILLING MATERIALS. 

at least has been made to elucidate the fact that any one of our materials 
is the best one for the special uses to which experience has taught us 
its properties have peculiarly adapted it. 

But supposing that we were actually limited to a choice of one 
kind of material. In that case we might, perhaps, choose what, in 
dental parlance, is known as the gold inlay — an alloy of gold, silver, 
copper, and zinc, cemented into the cavity. A discussion of this ap- 
pears in Chapters XIV, and XVII. This supposition, although quite 
imaginary, tempts speculation. 

Each material should receive the highest possible attention from 
the operator as it comes into his experience. • The object should 
always be to perfect oneself in the intelligent application and manipu- 
lation of materials; and this can best be done by regarding each, as 
it is indicated, as the ideal. This, indeed, it is, when once its prop- 
erties are found to harmonize with the needs of the case under treat- 
ment. 

In closing, perhaps it is well to reiterate that increase in technical 
proficiency is stimulated if accompanied by growth in a general under- 
standing of the eternal fitness of things — an appreciation of propor- 
tions and harmonies, not only in our own specialized branch of the 
great world of science and art, but in all that we can, by industrious 
study, bring from that world within the range of our intellect. The 
whole world of artistic endeavor — literature, music, design, painting, 
sculpture — every division of the industrial and liberal arts — teems 
with lessons for the worker in so exacting and delicate a profession as 
that of dentistry. "It is all triumphant art, but art in obedience to 
laws." Dentistry itself, regarded in its true light, must, in the minds 
of intelligent operators, come to be regarded as not the least among 
modern industrial arts. 

For one who acknowledges allegiance to this broader supremacy, the 
practice of our profession should, so far from narrowing a man's powers, 
continually expand them, and afford more and more intellectual 
satisfaction as he progresses towards the ultimate ideal of perfection. 



CHAPTER XIII. 
THE USE OF THE MATRIX IN FILLING TEETH. 

BY GARRETT NEWKIRK, M. D. 

Matrix — Definition of; Standard Dictionary: " That which con- 
tains and gives form to anything: as a plaster matrix for a cast. " From 
mater (mother). The term is used in connection with descriptive 
anatomy, geology, biology; also applied to forms for stamping coins, 
medals, types, etc. Pronunciation, ma'-trix or mat'-rix. PI. , mat'-ri-ces 
or matrices. "In dentistry — a strip used as a dam in filling side 
cavities." 

It will be observed that the primary use of the matrix is that of 
giving form to a new structure; in nature to a growth, in art or me- 
chanics to a building or product. In general the term applies to a 
product which is entirely new, a coin or medal or die. In dentistry 
we have a modified application of the term in that the matrix is used 
for the restoration of pre-existing forms that have been to a greater 
or less extent broken down. 

The term "filling" as usually employed, does not fully express our 
meaning. It is commonly said by the dentist that he has "filled" a 
tooth, as if the tooth were only a hollow form, a capsule, a membran- 
ous sac, or a shell like that of a cartridge. The incongruity is obvious. 
Simple cavities in teeth may be "filled, and to this class of cases the 
term should be limited. What we are really called upon to do in 
most cases is to build up, to restore, the parts of a structure that have 
been lost. This we do with a substitute material, joining it as best 
we may to the remains of the natural organ. 

We may liken the teeth, if we will, to a double row of monuments. 
The relation of these monuments is such that they are inter-dependent. 
The loss of one is felt by others. Each is dependent on its fellows 
for its own true position and usefulness. These monuments come to us 
broken, with every degree of injury, demanding repair or substitution. 
Some are like trees in Africa that have been honeycomed by the insid- 
ious white ant. Some are like houses half torn away by a cyclone or 
an earthquake. They are in part ruins. 

The restoration of these monuments in proper form and of material 
to endure is no simple problem. No two are quite alike, their forms 

255 



256 THE USE OF THE MATRIX IN FILLING TEETH. 

arc almost infinitely various. There are no plane surfaces. The study 
is one of curved lines. 

The mechanical matrix is a temporary wall, placed for the support 
of building material that is more or less soft and yielding. A familiar 
example is that of a board employed in the making of a concrete walk, 
which holds the material in form till it hardens. 

The use of the dental matrix is fourfold: 

First, to serve as a wall of resistance, so that under pressure the 
building material may be thoroughly condensed and joined to the 
tooth. Second, to give the general shape of restoration, with a suffici- 
ent excess of material for finish and form. Third-, in cases where plastic 
materials are used that require time for hardening and the matrix is 
kept in place till the new body has become fixed in its position. Fourth, 
to hold back the interproximal gum tissue, also the rubber dam, from 
the cervical border of a cavity, so that perfect contact of the build- 
ing material at that place may be assured. 

MATERIALS AND FORMS OF THE MATRIX. 

The ideal material is that combining the greatest strength with 
thinness and spring temper. It appears to be the consensus of opinion 
that no other substance possesses so many excellencies as very thin 
steel. - Ribbons of rolled or sheet steel, cut in suitable lengths, are 
best adapted for general use. 

For the first really practical band matrices made of thin steel, the 
profession is indebted to Dr. T. W. Brophy, who made up a "set" 
with an ingenious method of adaptation. These were placed on the 
market about the year 1886. 

Since that time many others have been brought out, generally under 
patent, though it is a question whether the original Brophy matrix did 
not cover the essential features of most of them. 

Tinned copper or German silver, rolled thin, are practicable ma- 
terials for band matrices, being easily adapted and soldered to fit spe- 
cial cases; for example, where the greater part of a molar or bicuspid 
crown is to be built up with amalgam, and where it is necessary to have 
the whole of the base encircled. In such instances it is not possible to 
obtain the best supporting matrix without making one especially for 
the case in hand. 

A good, practical, special band matrix may be made of the softer 
materials mentioned, as follows: A ribbon of proper width is cut half 
an inch longer than the measured circumference of the tooth. It is 
passed around and pinched together closely with pliers. A piece of 



MATERIALS AND FORMS OF THE MATRIX. 257 

binding wire is wound several times round the matrix ends at the line 
of juncture, and twisted tight. The projecting ends of the matrix 
band are now bent back and down upon the band proper and the ap- 
pliance is ready for use. To do this last part neatly it is well to pass 
the band over the anvil point or any suitable form so that a small ham- 
mer may be used for the flattening. 

Nearly always a band matrix made for the case in hand will have its 
basal circumference smallest. If the form of restoration has been 
right the body enclosed holds the matrix fast, and it must needs be 
disjointed or cut for removal. A continuous band matrix to be used 
and removed entire must be of necessity too large in its rootwise circum- 
ference or too small at the crown. If large enough to provide for the 
proximal contact points it will project far into the interproximal space, 
leaving a gap between the cervical edge of the matrix and the tooth. 

Theoretically, we are told that this condition is to be overcome 
by use of a wedge at the cervical margin, but this, particularly with 
a steel matrix, is easier said than done. The material resists stren- 
uously at both points, and the resistance reaches all around the band. 
Usually it is neither accomplished nor attempted. The operator fills 
the matrix as it is, leaving the building material projecting and ragged 
at the base, often impinging on the soft tissues. It is difficult afterward 
to remove this projection with chisels, files or corundum strips without 
laceration of the gums and pain to the patient. Therefore, it is very 
important that the matrix in its introduction should pass close to the 
tooth, between the hard and soft tissues, never impinging on the latter. 
It cannot be forced down midway in the interproximal space and 
afterward wedged forward to place without injury. It should go to 
its proper position at the first. 

Any sort of band matrix, continuous or jointed, whatever may be 
its merits has one disadvantage. It comes short of the ideal in that 
it requires the use of two interproximal spaces. This involves often 
difficulty of adjustment with loss of time, both in the putting on and 
taking off; and the extra, second space is taken where all available 
room is needed on the side to be built up. It is an advantage to have 
the sound side of the tooth crowded against its next neighbor with 
nothing between them. This was long recognized as a consummation 
to be wished, but it seemed necessary that in general the matrix must 
be continuous around the tooth to insure a rigid support. 

It seems to the writer, however, that by the use of the "Ivory" 
matrices and their accompanying clamps, encroachment on the second 
space may be avoided in the great majority of cases. Just as the 
17 



258 



THE USE OF THE MATRIX IN FILLING TEETH. 



"Perry" separator gets resistance on the inclined planes of the teeth 
instead of their disto-median axes, so the "Ivory" matrix clutch utilizes 
the inclined planes of the sound portion of the tooth to hold the matrix 
of restoration. The principle of the instrument is simplicity itself, 
and the mechanism highly ingenious. 

Of continuous band matrices — i. e., those that go round the tooth 
far enough to occupy two interproximal spaces — there have been many 




forms invented and placed on the market ; some of them patented. Cuts 
are reproduced here of the " Crenshaw, " quite popular in the East, and 
the "Hiniker," in general use on the Pacific Coast. 

There are others, any one of which may be of value, when ruled by 
skillful hands. 

A form of appliance that has been widely advertised and recom- 
mended is that which we may style the "double" matrix, consisting 



THE "HAND" MATRIX. 



259 



practically of two segments .backed together and used for building up 
the disto-occlusal wall of one tooth and the mesio-occlusal of another 
at the same time. Certainly the principle of such an operation is not 
just right. Such restorations it seems to the writer should be made 
separately — one at a time; for the two teeth are not immobile, each 
moving slightly with any exercise of force upon it. The matrix should 
be firmly fixed to the tooth that is being operated upon. In the in- 






FiG. 236. — Hiniker matrix. . 

sertion of the single " filling" the tooth and the material move together 
as one body, and the latter is in no wise disturbed. With two teeth at 
once, each possessing independent motion, this cannot, hold true — 
the material is likely to be in some degree disturbed. 

THE "HAND" MATRIX. 

This instrument consists of a short, thin blade, continuous with 
a shank and handle. It is a valuable instrument in certain places 
where the band matrix is hardly applicable. It is specially useful 
for giving form to fillings of cement or gutta-percha, and not infre- 
quently for amalgam restorations. Such a matrix may be readily made 
by the dentist himself out of any discarded instrument that has a 
sufficient body of steel for the blade — a spatula or thick chisel for ex- 
ample. The secret of success in getting the desirable tough spring 
temper consists in persistent hammering with the avoidance of high 
heat. It may be added also that any other than the finest of files 
should not be used in dressing down the blade to the required thinness. 

For use, with everything in readiness for quick manipulation of the 
building material, the matrix blade is placed in position and held by 



20O THE USE OF THE MATRIX IN FILLING TEETH. 

the left hand of the operator. It is seldom that an assistant can man- 
age it as well. The handle is given a strong twist, so that the rootward 
edge is held firmly up to the cervical margin of the cavity. The op- 
posite edge is held with equal firmness against the crown of the ap- 
proximating tooth. If either or both of the teeth are at all movable a 
considerable separation may be obtained by this steady twist of the 
handle. A sense of firm resistance, too, will be experienced while 
pressing the "filling" material home. The separation obtained 
should be equal at least to the thickness of the matrix, so that when 
it is withdrawn there will be sufficient fullness of material at the "con- 
tact" point. For restoring the disto-occlusal walls of a short crowned 
second molar, where it is sometimes impracticable to apply the rubber 
dam, and the work should be done quickly; and for incisors in making 
large restorations with cement, the hand matrix is a very useful instru- 
ment. 

A FEW DETAILS AS TO MANIPULATION. 

Success with the matrix often depends very much on previous 
preparation. Deep-seated cavities are frequently bordered by swollen, 
sometimes overhanging gums. It is nearly always better, after a free 
opening and more or less of preparation, to let these carry a filling 
of gutta-percha for some days. It is not unusual with the writer to 
have in one mouth several of these gutta-percha filled cavities waiting 
for the matrix and restoration. 

Before placing the matrix for an operation, if there is any doubt 
of its fitness it should be tried in tentatively, to ascertain whether it 
will pass as it should, close to the tooth wall and not upon the gum. 
Sometimes an ill-fitting matrix may be fairly adapted by pinching in 
the cervical edge with pliers. The Ivory matrices, however, are so 
shaped and may be so inclined in their introduction that they go to 
the right place easily in most cases. 

INTRODUCTION AND MANAGEMENT. 

It is commonly advised by experts that as a rule the matrix should 
not be completely tightened at the beginning, but only after the inser- 
tion of a third to one-half of the filling. Without doubt we may say 
that very many operators. do not take sufficient pains with that same 
first one-third. Of amalgam altogether too much is likely to be placed 
in the cavity at the start. Smaller pieces should be introduced at first 
and thoroughly condensed with smooth instruments all along the 
cervical wall and its junction with the matrix. This takes so much 
time that often a second "mix" of quick-setting amalgam is required 



REMOVAL. 261 

to complete the operation. Sometimes with extra dry alloy one may 
use a mallet with good effect. 

In the second half or last third of the filling, whatever the material 
employed may be, enough force should be exerted against the matrix 
to induce separation of the teeth by a space not less but more than 
the thickness of the band. If the teeth have been prepared by gutta- 
percha wedging, as above suggested, this necessary crowding apart 
is an easy matter. As stated before, there ought to be an excess of 
the new material to allow for final shaping, and there ought to be like- 
wise a separation of the teeth beyond the normal at the completion 
of the filling. This will permit the final contact point to come slightly 
below and away from the border of the occlusal surface, otherwise 
it will be a mere edge continuous with the occlusal surface, and not 
the rounded, finished knuckle of nature's plan. 

There would be an improvement at this point, no doubt, if the 
operator would take the pains to make in each matrix a sufficient con- 
cavity with contour pliers, to bring the filling nearer the ideal form. 
As it is, with any common form of matrix, the filling as the band leaves 
it shows only a straight profile from the cervical to the occlusal border. 
The contoured matrix, however, used for a plastic filling could not be 
removed at once without disturbing the form. It would need to re- 
main till the material had set. 

REMOVAL. 

With amalgam there are, as we know, advantages to be gained by 
leaving the matrix in situ till the material has become hard; indeed, 
it is very necessary to do so in cases where reconstruction has been 
extensive and the basal support relatively weak. But, on the other 
hand, there is something to be gained by immediate removal. This 
is one of the advantages of an open matrix like the " Ivory. " When 
the clutch is loosened it "lets go." It is readily straightened, being 
flexible, and touches the tooth or filling only at the point of contact. 
With the lightly oiled surface a band should always have it is easily 
removed by gentle manipulation. Then, with a properly shaped blade, 
half knife, half burnisher, a trimming and close condensation of the 
material may be made all along the edges. I believe that perfect bor- 
ders can be made in this manner with greater certainty than is possible 
otherwise. 

EMPLOYMENT OF THE MATRIX FOR GOLD RESTORATIONS. 

We know what the bevel of a margin should be for the reception 
of gold. We know that for the proper condensation of gold over such 



202 THE USE OF THE MATRIX IN FILLING TEETH. 

a margin the instrument would better have free play; and we know that 
it is well to have visual as well as mechanical access to the area involved. 
There is no denying that the matrix does shut off seeing along the very 
lines where seeing is desirable. If we permit a loose adjustment of the 
matrix in order to see the margins it is of little use. It is likely also to 
crowd upon the gum tissue, to draw the edge of the dam from the tooth 
and induce leakage. If closely adjusted, the matrix forms with the 
beveled margin a sharp, acute angle, into which the gold must be forced 
accurately and condensed, else there is left an imperfect line of union. 
We cannot be as certain with as without the matrix that the gold is 
being adapted accurately at every point. Undoubtedly there are 
operators who have learned with much of patience and experience to 
obviate the risk; who can apply the matrix over a deep-seated cavity 
and make a good restoration from start to finish. But such operators 
the writer believes to be exceptional. It is a fact of experience that we 
are often called on to renew or repair fillings that have been so inserted 
which have failed at the cervical or cervico-lingual or cervico-labial 
borders; and we find others that are spongy or pitted or grooved in those 
places. Let it be understood, however, that after a substantial body 
of gold has been placed along the wall and angles of the cavity, then 
the matrix may be of service as a guide to the general form of building, 
especially for the full extension and thorough condensation of the 
"knuckle" at the contact point; and possibly the work may be done 
more rapidly. 

If one is determined to take the risk, whatever it may be, of using 
the matrix "from start to finish" for contour restorations, he must 
familiarize himself with the properties and manipulation of non- co- 
hesive gold. It is the chief dependence of successful operators for 
the basal third or half of the restoration. 

GUTTA-PERCHA FILLINGS. 

For the insertion of these the matrix has a well-defined use. Aside 
from those cases wherein it is necessary to crowd away the gum for a 
subsequent operation, the margin of a gutta-percha filling should be 
carefully made like any other. Patients often suffer discomfort and 
sometimes real injury from carelessly made gutta-percha fillings. 
It is better to make a filling of good form to begin with than to crowd 
in an ill-defined mass to be trimmed up afterward, and for this purpose 
the "hand" matrix is usually well adapted. 



CHAPTER XIV. 
INLAYS. 

BY C. N. JOHNSON, M. A., L. D. S., D. D. S. 

The Principle. — To repair a carious or abraded cavity in a tooth 
by the inlay method the operator adapts a piece of heavy foil, either 
platinum or gold, to the cavity so that it fits perfectly, thus reproducing 
the form and outline of the cavity in metal; and in the matrix so formed, 
removed from the mouth, he builds a filling of porcelain or gold and 
cements this in the cavity. In the more recent developments in gold 
inlay work a wax model is made in the cavity, and this is reproduced 
in gold. The principle is different from that of the ordinary filling, 
the latter being adjusted piece by piece into the cavity in the tooth, 
the entire operation being performed in the mouth; while with the 
inlay much of the work is done outside the mouth and without the 
necessity of the patient's presence. This is a very great advantage 
of inlay work and has led in a large degree to its popularity. The 
relief from the tedium of long and sometimes painful sittings has 
been a source of great satisfaction not only to the patient but to 
the operator as well. There is less nervous tension and altogether 
a greater measure of comfort in doing inlay work than in such oper- 
ations as large gold fillings, and this phase of the subject has appealed 
very strongly to patients. 

INDICATIONS FOR THE USE OF INLAYS. 

That inlays have become an important factor in reparative proc- 
esses in operative dentistry there can be no question. There is still 
some difference of opinion as to the precise range of their applicability, 
but for certain well-defined cases their utility is no longer in doubt. 
It must, therefore, be apparent that no dentist can practice to the best 
advantage for himself and his patient without an understanding of this 
work. There are many cases of affected teeth that can be better 
preserved by this than by any other method. In cases of extensive 
decay it may frequently be made to save a tooth which otherwise 
would be condemned to crowning, and on general principles the 
longer a tooth can be saved without a crown the better it is for the 
patient. 

263 



264 INLAYS. 

From the nature of their method of manufacture inlays are restricted 
in their use to cavities which will admit of the matrix or wax being 
inserted and removed without distortion, or cavities which may be 
made of such a form without an unwise sacrifice of sound tooth tissue. 

Porcelain inlays are indicated chiefly in cavities exposed to view 
in talking, laughing, or singing. It should be the highest aim of art 
in dentistry to conceal the evidence of our operations from public 
view, and the conspicuous display of gold so frequently seen in the 
anterior teeth of patients speaks of a lack of taste which is something 
of a reflection on the profession. Fortunately this display is less 
prominent than formerly, and this in large measure is due to the 
introduction of porcelain inlay work. With porcelain an operation 
may be made which is not conspicuous at conversational distance 
from the patient, and in some instances the porcelain may be shaded 
to match the enamel so perfectly as to defy detection even on reason- 
ably close observation. This is a great step in advance so far as 
the art side of our calling is concerned, and every dentist should equip 
himself to take advantage of it. 

But this work has its limitations which should be recognized by 
every conscientious operator. The physical characteristics of porce- 
lain are in some respects very much against its extended use, particu- 
larly in positions where the stress of mastication comes forcibly upon 
it. Porcelain is brittle and will fracture easily. It is therefore contra- 
indicated in cases where the filling must be made with thin margins 
or in small bulk. It is true that in the anterior part of the mouth 
where esthetic considerations are very important it is frequently 
justifiable to take some chances of its fracture and place it in positions 
of prominent exposure even with some risk of failure. Patients are 
often willing to take this risk for the sake of the improved appearance 
over any kind of a metal filling, and where there is a perfect under- 
standing between operator and patient as to the possibilities of failure 
porcelain may be given a rather wide range of application in the 
anterior teeth. Porcelain inlay work has not been sufficiently long 
in general use to afford the necessary data upon which to base reliable 
judgment as to its probable permanence, and many of these cases 
where great risk was apparently taken the service of the inlays has 
been surprisingly satisfactory. It may also be stated that in many 
other cases where the same care has been exercised in their manu- 
facture, and where conditions would seem to favor their utility they 
have proved a grievous disappointment. It is this element of uncer- 
tainty with inlays which has made many of our conservative practi- 



INDICATIONS FOR THE USE OF INLAYS. 265 

tioners look with disfavor upon the work, and yet their demonstrated 
utility in so many cases is sufficient to argue strongly in their behalf. 

It is probably true that much of the failure has been due to imper- 
fect methods of manipulation and to a lack of knowledge of the under- 
lying, principles of the work, as well as to faulty technique in carrying 
it out. Another uncertain factor has been the cement. This material 
has proved itself peculiar in its behavior under various conditions 
and some of its peculiarities have not been well understood. In 
addition to this, much of the cement used for inlay work in the past 
has been made for fillings and for cementing crowns without regard 
to the peculiar requisites for inlay work. Neither have the correct 
principles of cavity preparation for inlays been generally recognized 
or put in practice. 

In short the work has had to pass through the experimental stage 
of a new line of effort and has suffered accordingly, but these factors 
of f ailure are rapidly being eliminated and we may confidently look 
forward to more assured success since the principles are being better 
understood and the technique systematized; though with porcelain 
inlay work it must not be forgotten that it will always have the one 
serious limitation of friability of the material itself. 

Gold inlay work has a much wider range of usefulness so far as 
serviceability is concerned than porcelain on account of its great 
strength, and it should be used quite generally wherever inlay work is 
indicated in places not exposed to view. Gold may be made to 
protect frail walls of enamel if necessary and the material itself may 
be extended into thin margins without danger of fracture. 

To specify the particular classes of cavities where inlay work is 
indicated and draw a distinct line of demarcation between the indi- 
cations for fillings and inlays is difficult, owing to the varying con- 
ditions which are presented in different cases. The preference of the 
patient must sometimes be considered, though it is not well to allow a 
whimsical prejudice to influence the operator to do a certain class of 
work under conditions where it is manifestly contra-indicated. It 
may be said in general that porcelain inlays are indicated in all cavities 
exposed conspicuously to view in cases where esthetic considerations 
are very important, such as cavities in the labial or buccal surfaces of 
incisors, cuspids and bicuspids, cavities in the proximal surfaces 
of those teeth where there is much exposure, and in contour operations 
involving two surfaces where a display of gold would be objectionable. 

Gold inlays are indicated in large restorations in bicuspids and 
molars, in cavities far back in the mouth where the problem of insert- 



200 INLAYS. 

ing an ordinary filling is difficult, and cavities in the buccal surfaces 
of molars where the decay has extended under the free margin of the 
gum. Employed in these cases gold inlays are very useful and may 
be given a wide range of service, but this will still leave a large class 
of cavities where the ordinary rilling has its legitimate field and where 
no inlay can do equal service. 



CHAPTER XV. 
PREPARATION OF CAVITIES FOR INLAYS. 

BY C. N. JOHNSON, M. A., L. D. S., D. D. S. 

When inlays were first introduced the general impression given 
the profession that the adhesive properties of cement could be relied 
upon to hold the inlay in place irrespective of much depth to the cavity 
led to the formation of cavities too shallow and with insufficient atten- 
tion to the principle of mechanical anchorage. Inlays should be 
anchored upon the same general mechanical plan as fillings, the only 
difference being in the details. It will of course be recognized in the 
beginning that cavities for inlays must be so formed that the matrix or 
wax may be lifted from the cavity without distortion, and this idea being 
prominent in the mind of operators caused them in many instances 
to make the walls of their cavities too flaring, with the orifice much 
wider than the interior. This resulted in attenuated edges to the 
inlay and frequently to a lack of definiteness of form, leaving the cavity 
more or less saucer-shaped. This is wrong in principle and has 
quite generally proved a failure in practice. Cavities should be made 
with some depth and with walls so formed that the inlay will remain 
seated without tilting or rocking under pressure even before it has been 
cemented. 

In opening up cavities it is true that there are many cases where the 
orifice must be quite widely extended to admit of entering a matrix or 
wax into the cavity and removing it. This often involves cutting much 
sound tooth tissue, particularly in proximo-occlusal cavities in bicuspids 
and molars, where the decay in the proximal surface may have ex- 
tended much wider bucco-lingually in the gingival region than it 
has nearer the occlusal surface. It will be seen at once that to fit 
a wax model to such a cavity it must be extended bucco-lingually very 
freely at the point where the proximal surface joins the occlusal to 
bring it on a line with the cavity further rootwise. The practitioner 
who purposes using inlays in these cases must have the will to cut 
quite extensively, and there are many instances where the loss of sound 
tooth tissue is so very great that the discriminating operator will 
decide upon inserting a filling instead of an inlay. This is one factor 

267 



268 PREPARATION OF CAVITIES FOR INLAYS. 

in the choice between inlays and fillings which has not received suffi- 
cient consideration. While it is true that in the preparation of cavities, 
whether for inlays or fillings, we are frequently called upon to remove 
sound tissue for better access to the cavity and to establish marginal 
outlines at points where recurrence of decay will not take place, yet 
it is unjustifiable to sacrifice large portions of sound tissue in locations 
of practical immunity from decay in order to bring the cavity within 
the requirements for inlay work. In many of these cases a filling may 
be inserted to better advantage and with less injury to the tooth. 

One cardinal principle in the formation of cavities for porcelain 
inlays is that they should be so shaped if possible as to leave no thin 
margins to the porcelain. A thin margin usually means a fractured 
margin in a short time. With cavities for gold inlays the exact opposite 
is true. One of the chief virtues of gold inlays is that the enamel 
margins may be freely beveled and the gold allowed to lap over them — 
a relatively thin layer of melted gold being sufficiently strong for 
ample protection to the enamel. It is with this idea in mind that the 
following detail of cavity formation for the different classes is sug- 
gested. 

Cavities in the labial surfaces of incisors and cuspids, and the 
buccal surfaces of bicuspids and molars. The first essential in the 
preparation of these cavities is to open the cavity freely by breaking 
down all enamel undermined by decay. The axial or pulpal wall 
should be made perfectly flat so that the inlay will have a definite 
seat to rest upon. This is conveniently done with an inverted cone 
bur stood with its end looking toward this wall, and carried laterally 
across the floor of the cavity. There should be an angle formed 
between the axial wall and the surrounding walls, not a perfectly 
right angle so as to leave the surrounding walls parallel, but very 
nearly so. If these walls were perfectly parallel it would manifestly 
be impossible to fit a matrix and remove it, but the nearer they approach 
to this the more securely will the inlay be anchored, and the less neces- 
sity for relying on the cement as an adhesive agent. Cement should 
be used in the capacity of a sealing material between tw T o joints and 
not as a glue to hold the inlay to the cavity. In short the cavity should 
be so formed that there shall be some frictional retention against the 
surrounding walls, the inlay in many instances going to place with 
a snap. When cavities are formed along these lines there will be 
less trouble from inlays dropping out. 

It might be imagined that the fitting of a matrix to such a cavity 
would be very difficult but this is found in practice not to be so, and 



PREPARATION OF CAVITIES FOR INLAYS. 269 

even if it did slightly complicate this part of the operation it would 
be justifiable on account of the greater security of the inlay. 

There should be no beveling of the enamel margins for porcelain 
except as the slight divergence of the surrounding walls at the orifice 
of the cavity forms a bevel. In the use of the inverted cone bur for 
forming the axial wall if the sharp angle of the bur should undercut 
the surrounding walls they may be trued up with a chisel or with a 
fissure bur stood with its end looking toward the axial wall and cut- 
ting with the side of the bur. The outline of a cavity formed as just 
indicated is shown in the two sections of an incisor, Fig. 237, longi- 
tudinal, and Fig. 238, cross-section. 

In bicuspids the form of the axial wall is sometimes different 
from this on account of the difference in the form of the tooth. If 
the axial wall were cut perfectly flat in some cases of extensive decay it 
might result in exposure of the pulp and so it should be given a convex 







Fig. 237. Fig. 238. Fig. 239. Fig. 240. 

form as indicated in the cross-section of a bicuspid, Fig. 239. This 
form facilitates the firm seating of the inlay fully as w T ell as the flat 
form, and in some instances furnishes a more secure anchorage. 

In extensive penetration of caries where the cavity runs under a 
strong wall of overhanging tooth tissue and it is deemed undesirable 
to cut this wall entirely away, it may be permissible to excavate the 
cavity perfectly and fill the undercut with cement. After this has 
become hard the cavity may be prepared as usual. This practice 
is not often feasible on account of the fact that ordinarily when decay 
undermines a w r all it does so in such a way as to w T eaken it beyond the 
possibility of retaining it with safety. 

Upon broad surfaces such as the buccal surfaces of molars we 
frequently find decay running along over a considerable area with 
little penetration into the tooth, and in these cases if the cavity is 
formed on correct mechanical lines with flat seat and proper angles 
it need not be made very deep. But an inlay for such a cavity should 
be of strong material and it is usually best in all buccal cavities of 
molars to insert gold inlays in preference to porcelain. 



270 PREPARATION OF CAVITIES FOR INLAYS. 

Simple cavities in the proximal surfaces oj incisors and cuspids. 
Those cavities must be opened sufficiently to the labial or lingual to 
admit of fitting the matrix, and it is therefore necessary to cut away 
one of these walls quite freely; though the ample separation of the 
teeth in advance of the operation will in some measure dispense with 
this necessity. The same provision for seating the inlay firmly in 
place should be made in these cavities as in others and the axial wall 
should be made as flat as possible. If the labial wall has been cut 
away and the lingual wall remains standing with sufficient integrity 
to admit of it being left, there should be an angle formed between it 
and the axial wall, and even where the lingual wall must be removed 
it will be found possible to make a point angle in the gingivo-linguo- 
axial region. The gingival wall should be made at nearly right angles 
with the axial wall and almost parallel with the incisal wall, which 
should also join the axial wall at an angle, so that the inlay will 
lock between the incisal and gingival walls as if in a box. Fig. 240 
illustrates the labial surface of an incisor with the marginal outline 
of the cavity indicated, and the dotted lines showing the interior form 
of the walls. 

In cases where there has been much breaking down of the lingual 
wall with a strong labial wall standing, the cavity should be opened 
mostly to the lingual and the inlay inserted from this direction. In 
these cavities an angle should be made in the gingivo-labio-axial 
region so as to form a flat seat of resistance at this point, which will 
receive most of the stress brought to bear upon such an inlay. 

Cavities in the proximal surfaces oj the anterior teeth involving 
the incisal angle. These cavities present a more difficult problem 
for porcelain to meet than any of those where porcelain inlays are 
indicated, and yet their exposed positions often call for this kind of 
restoration. It is therefore necessary to study very carefully the forms 
that shall be given these cavities for the most secure anchorage and 
the greatest strength to the porcelain. The operator must individual- 
ize his cavities and take advantage of every possible opportunity 
presented by the peculiarities of the case to gain depth to the cavity 
and bulk to the inlay. 

It will usually be found that to gain security of anchorage some 
form of step must be made in the incisal region, and yet there are 
certain cases which do not lend themselves readily to this method 
of treatment. Ordinarily the step is made by cutting across the incisal 
edge at right angles to the proximal portion of the cavity making 
approximately an L shape to the inlay, but sometimes it is not ex- 



PREPARATION OF CAVITIES FOR INLAYS. 



271 



pedient to cut away the angle of the enamel in this manner. This is 
particularly true of those cases where the decay has involved the 
lingual surface far in advance of the labial in upper incisors leaving 
little tissue in which to form a step. It is also true in some instances 
where there has been a simple proximal cavity of shallow depth in 
either an upper or lower tooth and the incisal angle has fractured off 
following a check in the enamel leaving a clean sound surface of 
tissue along the axial wall with the enamel in perfect condition in the 
incisal region. These are cases which do not call for much incisal 
exposure to stress and it would seem too radical a procedure to cut 
away the incisal enamel, besides increasing the exposure. If the 
teeth in these cases are well separated a cavity may be prepared by 
cutting a shoulder in the axial wall looking toward the incisal and 
about one and one-half millimeters from the incisal edge, as indicated 
in Fig. 241. This should be supplemented by a rather deep and strong 





Fig. 241. 



Fig. 242. 



Fig. 243. 



anchorage in the gingival region, and if the teeth are sufficiently 
separated the inlay may be slipped into place laterally. This form 
of anchorage is of course not the strongest from a mechanical point 
of view where great stress is exerted on the inlay, but in a somewhat 
close observation of many cases in practice it has proved sufficiently 
satisfactory to recommend its use in the class of cavities indicated. 
Where the step anchorage is employed it is usually best to shorten 
both labial and lingual plates of enamel at least half way across the 
incisal edge (Fig. 242, labial view) , though this is not invariable. Some- 
times the labial enamel may be left standing in upper incisors provided 
sufficient bulk can be given the porcelain in the step. In either case 
the lingual plate should be cut away more than the labial, and this is 
particularly true near the termination of the step. At this point the 
lingual aspect of the step should be made to dip rootwise quite per- 
ceptibly to provide an interlock to the inlay (Fig. 243, lingual view). 
Care should be taken that there are no thin edges left to the inlay 
in any of its outline and this is accomplished by cutting the enamel 
with little or no bevel. It is also possible in some instances to add 



272 PREPARATION OF CAVITIES FOR INLAYS. 

to the bulk of the porcelain in upper teeth, and thus increase its 
strength in the region of the step, by building it fuller lingually than 
the tooth originally was. The relation of the lower incisors will 
often admit of this and in some instances it is advisable to slightly 
shorten the lower tooth to give the needed space. 

In the gingival region provision should be made for a broad seat- 
ing of the inlay. The gingival wall should be flat and as wide mesio- 
distally and long labio-lingually as the available tooth tissue will 
permit. No undercutting is of course permissible but the labial 
and lingual walls may be made to extend from the gingival w r all in a 
very nearly parallel direction. This will give a box-like form to the 
cavity in this region and result in security to the inlay when cemented. 

Cavities for the restoration of incisal tips. It is sometimes found 
practical where the incisal portion of an anterior tooth has been 
marred by faulty development, so as to be dwarfed and unsightly, to 
restore the end w 7 ith porcelain. It is also possible in some instances 








Fig. 244. Fig. 245. Fig. 246. Fig. 247. Fig. 248. 

to do this where the incisal portion of an incisor has been broken off 
by a blow, though the cavity preparation for the two is entirely differ- 
ent. In the first instance there is usually a thin projection of tooth 
tissue standing on the end of the tooth as if the enamel had been 
stripped from it, and this may be utilized as a tenon over which the 
inlay may be mortised (Fig. 244, longitudinal section of an incisor mesio- 
distally, Fig. 245, longitudinal section labio-lingually). The shoulder 
where the perfect enamel begins and against which the inlay is fitted 
should be cut at right angles to the tenon, and the latter so trimmed 
that the matrix may be fitted over it and removed without dragging. 

In the case of a fractured tooth leaving the end flat the problem 
of anchorage is greatly complicated. Retention must be gained by 
drilling into the fractured surface and the danger of approaching the 
pulp is always a factor in the case. If the fracture has not occurred 
far rootwise a groove may be made running mesio-distally across the 
tooth (Fig. 246) , shallow in the center to avoid the pulp and deeper at 
each extremity where it passes mesially and distally of the pulp 



PREPARATION OF CAVITIES FOR INLAYS. 273 

(Fig. 247). If the fracture has extended so near the pulp as to reach a 
thick part of the tooth so that the labio-lingual width of the fractured 
surface will permit it, two grooves may be made, one to the labial 
and one to the lingual of the pulp, and these should join the labio- 
lingual grooves at either side (Fig. 248). All grooves for this purpose 
should be made flat at the base and as broad and deep as the tissue- 
will permit. 

Cavities involving the proximal and occlusal surfaces of bicuspids 
and molars. These complex cavities are usually better managed by 
the use of gold inlays than porcelain and the detail of cavity formation 
herein suggested is in accordance with this idea. The most serviceable 
of all inlay work is in connection with the large restorations frequently 
necessary in these cases, and the operator should study carefully the 
possibilities of inlays in those positions in the mouth where the diffi- 
culty of inserting large fillings of foil has frequently proved a serious 
physical and nervous tax on patient and operator. 

As has already been intimated the preparation of these cavities 
involves a wide extension bucco-lingually of the proximal portion of 
the cavity as it reaches the occlusal, and wherever a step can be made 
in the occlusal surface at right angles to the proximal the chief reliance 
for anchorage should be in this step. This is particularly true of 
bicuspids where the bulk of tissue for anchorage in the proximal 
region is not so great as in molars. The step should be given a dove- 
tailed or interlocking form so as to avoid any possible tipping of the 
inlay and this may usually be accomplished in one of two ways, depend- 
ent upon the form of the tooth. Where the cusps are prominent 
and the depressions between them deep it will usually be found that 
there is an appreciable concavity at the termination of the step most 
remote from the proximal cavity, and in this instance the step at this 
point may conveniently be made much wider bucco-lingually than it 
is midway between the cusps. The effect is to dovetail the step portion 
of the inlay against any possibility of tipping. (Fig. 249.) Where the 
occlusal surface is more nearly flat with little prominence of the cusps 
and almost no depression between them, the interlock may be secured 
by deepening the termination of the step rootwise as shown in Fig. 250, 
a mesio-distal, longitudinal section of an upper bicuspid. 

The same provision for a flat gingival wall in the proximal portion 
should be made as in incisors, and the buccal and lingual walls should 
extend from the gingival in nearly a box-like form. If the cavity is 
prepared in this way and the inlay properly fitted it will snap into 
place with a frictional retention against the walls which adds greatly 
18 



274 



PREPARATION OF CAVITIES FOR INLAYS. 



to the sense of security. Such an inlay will not rock or tip on pressure 
even before it has been cemented. 

In case the enamel on the occlusal surface leading from the cavity 
is perfect and it is deemed not advisable to cut into it to form a step, 
retention against tipping may be secured by making the cavity slightly 
wider bucco-lingually at the axial wall than it is at the dento-enamel 
junction (Fig. 251, cross- section of a lower molar). This forms a dove- 
tail and in cases where there is sufficient bulk of tooth tissue to work 
on it may be done without weakening the walls. It is of course 
apparent that the only direction in which a model or inlay can be 
removed from such a cavity is toward the occlusal surface. 

In other cases where the dentin is so involved in the occlusal region 
as to leave the axial wall greatly concave and no foundation for a step, 
an interlock may be gained by shortening one of the cusps and build- 
ing the inlay over it (Fig. 252, lingual surface of a bicuspid). It will 
be found in these cases that the dentin is quite extensively dissolved 




Fig. 249. 




Fig. 250. 




Fig. 251. 




Fig. 



from under the enamel as it arches over the cusp and the wall is made 
more secure by cutting down the cusp and protecting it with gold. 
This may be done with both cusps if necessary where there has been 
much undermining of the enamel, and even this extensive restoration 
may frequently be necessary without the pulp being involved. These 
are the cases which heretofore have been quite generally consigned 
to crowning, but an inlay restoration such as just indicated where 
even the entire occlusal surface is reproduced in gold is in every 
respect preferable to a crown. And this is not only true of these cases 
but of others still more extensive where the mesial, occlusal, and distal 
surfaces are involved in the same tooth, requiring a restoration of all 
three with the gold overlapping the buccal and lingual walls. (Fig. 253, 
lower molar, buccal surface.) 

The general form of the cavity in such cases must of course be 
governed by the conditions presented. Weak or overhanging enamel 
should be ground away quite freely for the double purpose of securing 
a firm foundation and for thoroughly opening up the cavity. The 



PREPARATION OF CAVITIES FOR INLAYS. 



275 




principle of the flat seat for the inlay to rest upon should be maintained 
as largely as possible, because of the necessity for security against 
dislodgment under the severe stress of mastication to which such 
restorations are subjected. The enamel margins should be beveled 
away quite freely with the utmost confidence that the gold will form an 
adequate protection to them. __ v ,,-- s 

In case the pulp is dead advantage may be taken of 
the pulp chamber for anchorage after the canals have 
been filled, but in the event of this additional anchor- 
age not being required the chamber may be filled with 
cement and this leveled to form a flat seat for the inlay. 

Cavities in the occlusal surfaces of bicuspids and 253 * 

molars. It is a very rare condition which calls for an inlay in the 
occlusal surface of a bicuspid unless it involves some other surface. 
A simple occlusal cavity can be more judiciously managed with a 
filling than an inlay, and it is only in molars with cavities of appre- 
ciable extent where it is judicious to make occlusal 
inlays. The preparation of these cavities is not com- 
plicated. The floor or pulpal wall should be made flat 
so as to be at right angles to the stress of mastication, 
and the surrounding walls should be nearly parallel to 
make a mortised effect to the inlay (Fig. 254, section 
of a lower molar). 
In cases where there has been an extensive involvement of the 
tissue undermining the occlusal enamel leaving it frail, it may be 
ground down slightly past the marginal ridge and the entire occlusal 
surface reproduced in gold (Fig. 255). 

The technique of cavity preparation for inlays is 
quite simple and the operation altogether more accept- 
able to the patient than for fillings. There is no 
necessity for applying the rubber dam and this to many 
is a great relief. The cutting is mostly done with 
chisels, excavators, and such rotary appliances as 
stones, wheels and disks. The only necessity for the 
use of burs in large cavities is in sharpening up some of the line 
angles, and to flatten the w r alls left rounding by the stones. The 
fact that the grinding may be done under moisture reduces the 
pain to the minimum, and this is a great recommendation for this 
class of work. 




Fig. 254. 




Fig. 255. 



CHAPTER XVI. 
THE PORCELAIN INLAY. 

BY VV. A. CAPON, D. D. S. 

The eventual success of porcelain as a filling for teeth depends 
upon thorough consideration of two primary principles, viz., founda- 
tion and adaptation. The first term applies to cavity preparation, 
the second to matrix formation, and they are closely allied in im- 
portance. The consideration of the former by a preceding chapter 
allows the matrix to become my first topic. The metals used for 
matrices in porcelain inlay work are made of either platinum or gold 
foil and their respective value for this purpose is usually an argumenta- 
tive point whenever the subject of high or low fusing porcelain is 
discussed. Adherents of high fusing porcelain have no choice except 
platinum while the advocates of lower heat material can use either 
gold or platinum. Platinum has for its recommendation adaptability 
and stability of form, together with its great resistance to high heat, 
thus dispensing with the necessity for an investing material to keep 
its form. The virtue of gold is its ductility and easy adaptability to 
floor and walls of cavity, but this very softness in the majority of cases 
renders an investment necessary, thus precluding any trial fitting or 
reburnishing which is of so much assistance especially to the beginner. 
It being my intention to describe the use of high fusing porcelain 
particularly, I have no alternative of a choice of metals for a matrix 
even if so desired, and will consider the subject from this point of view. 

The difficulties connected with making a matrix are somewhat 
regulated by the position of the cavity and the amount of working 
space in its immediate vicinity, therefore it may simplify the subjects 
to divide them into three grades as follows : 

i. Labial and buccal cavities. 

2. Proximal cavities in anterior teeth with lingual surface not in- 
volved. Gingival cavities curving well to the proximal. 

3. Proximal cavities in incisors involving lingual surface, prox- 
imo-incisal restorations, distal surface of cuspids, mesial surface of 
first and second bicuspid and first molar. 

Sufficient space between teeth is imperative with this class of 
operations because porcelain is unyielding and cannot be forced to 

277 



278 



THE PORCELAIN INLAY. 




position without risk of chipping edges. The matrix must 
come from the cavity without change of form and fre- 
quently there is plenty of space for the inlay when finished, 
but owing to necessary excess of matrix material it locks 
itself when there is apparently sufficient space. The im- 
pression of the cavity or matrix is made with gold foil No. 
40 or pure platinum gauge 1/1000 in. or .001 in. thick- 
ness — thoroughly annealed. In these days of inlay requi- 
sites this material is kept ready for use by all dental dealers, 
but it should not be handled much before using and it 
should be pure. If greater softness is required give it a 
high heat in the furnace muffle. I emphasize the word 
pure because iridium and platinum are naturally alloyed 
and as iridium is the most difficult metal of the platinum 
group to eliminate, this fact may account for the variance in 
softness in different purchases. The proper thickness of 
Dili the metal has been a point of considerable discussion, but 
it is now generally conceded that 1/1000 is the correct 
thickness for most operations. It may sometimes be slightly 
1 heavier, but never thinner. Many argue that if 1/1000 is 
good 1/2000 must be better because of the minimum amount 
of metal at the edges, forgetting or not knowing that burnishing 
reduces thickness to a lighter gauge. 

Labial cavities in central incisors are in the first grade, there- 
fore a detailed description will be more easily understood. 

The foil is cut sufficiently large to allow holding against adjoining 
teeth, and somewhat diamond shaped, the extreme ends being held 



JJ 



THE PORCELAIN INLAY. 



279 



firmly by the first and second fingers of the left hand, leaving the right 
hand free to use the instruments for burnishing. 

My preference is for few and simple instruments such as two or 

J three sizes of rubber tips and some 
amalgam burnishers. 






'■If 







*W*T\ 



■s> 



6 



Special instruments such as 
those designed by Dr. W. T. 
Reeves, and Dr. C. N. Thompson 
have extensive use and fulfill the 
8 requirements desired. (Figs. 256 
and 257.) 
Whenever possible it is well to give the outline of the cavity 
by the rubber points or spunk held by ball tipped pliers pressed 
firmly over the cavity, stretching the metal with safety, then 
rotating a ball pointed instrument with gentle pressure, com- 
mencing with a large size, following with smaller ones until 
the metal is fairly well adjusted; then use small pieces of 
spunk, chamois skin or camphor, packing tightly. It is now 
safe to use the other hand and with it hold the matrix in 
place with a blunt instrument pressing the packing, then 
burnish edges thoroughly, but not roughly for fear of tearing. 
A break on the cavity edge means a new mold while one at the 
bottom of the matrix is of no moment. Remove spunk or 
whatever has been used as an assistant and carefully release 
the matrix which is now ready for the porcelain. If inad- 
vertently there is an undercut in the cavity sufficient to lock 
the matrix, gently force it out, then replace and reburnish the 
edges, not touching the interior, thereby making a change of 
the cavity unnecessary. 

The making of a matrix for a proximal cavity requires more 
skill and practice. The foil should be carried well above the 
gingival margin of the cavity and if the gum is even with it the 
edge of the metal should be turned to look toward the proxi- 
mating tooth and lie over the gum, giving a sure working sur- 
plus. Rubber points are not much used in these places, there- 
fore take the flat end of a burnisher and press across the 
cavity edges, gently forcing the foil to position assisted by 
small squares of spunk. The burnishing and general procedure is 
the same as for a simpler cavity except that usually surplus foil is 
in the way if both labial and lingual surfaces are burnished flat to 
the tooth, therefore if drawing from the labial side, have the lingual 



THE PORCELAIN INLAY 

surface approximately burnished, take out and cut surplus off, then 
replace and get outline more perfectly and thus save a probable 
twisting of the matrix caused by an excess of material. If the cavity 
has greater presentation toward lingual surface the same rule is 
applied. Many practitioners suggest that much assistance can be 
gained by holding matrix in place with rubber dam, gold beater's 
skin, or china silk, and burnishing the matrix through these materials. 
Occasionally they have value. 

Some four years ago Dr. Allen, of Kansas City, added gum- 
camphor to our equipment as an assistant in making a matrix and 
it is most excellent when used properly, but many operators make 
the mistake of using it everywhere, forcing it in the cavity when the 
matrix is unprepared, and the result is an aperture from edge to edge, 
therefore it is well to have the cavity w r alls fairly outlined before using 
it. After the matrix is made it is recommended that it be thoroughly 
cleansed by placing it in alcohol which will cleanse it of saliva or blood 
if camphor packed. The action of alcohol wall dissolve the mass so 
it will drop out. Passing it through an alcohol flame will burn it 
out leaving no residue w T hich is one of the recommendations for using 
this material for packing; how r ever, if gold is being used it is safer to 
use alcohol alone. After the matrix is cleansed clasp the surplus 
portion firmly with a pair of straight fine pointed tweezers and fill 
the mold with the shade of porcelain chosen, which is mixed with 
clean water or alcohol or a mixture of both and applied with a fine 
pointed sable pencil brush and the little lump of stiff porcelain is 
gently patted or jarred to place. The edges of the cavity form 
are traced clean with point of brush and the embryo inlay is laid face 
down on absorbent paper or a clean napkin which abstracts the surplus 
moisture. I prefer applying the first piece so dry that it is difficult 
to pick up with the brush. It is at this point that the advantage of 
a sable brush is noticed because it holds a point without drooping 
while camel's hair droops and has no stability. 

If the matrix should have a pierced or broken bottom which is 
almost unavoidable in a deep cavity, fill it as if it were intact and 
unless the aperture is extremely large it is surprising how much tap- 
ping or forcing is required to make the porcelain pass through; however 
under all circumstances it is a safe rule to turn the matrix bottom 
side up and examine it closely and trace it with a clean brush, other- 
wise a very small particle of porcelain left unnoticed and becoming 
fused will make the work to this point useless. 

If a break is made on the cavity edge of the matrix, condemn 



FUSING. 28l 

it and make another, as it is impossible to have a perfect margin unless 
the matrix is intact on that margin. 

When excess of moisture has been removed, place it on a metal 
or fire clay tray at the mouth of the furnace, gradually pushing it to 
the interior, using care that too quick evaporation does not loosen 
porcelain from walls of the matrix. If this occurs a refilling of the 
mold is the only alternative. Close the door of furnace and the 
process of fusing has commenced. The shrinkage of porcelain plays 
a prominent part in all such operations and unfortunately it keeps 
the most experienced "guessing," therefore those unfamiliar with 
the work are handicapped at the beginning by a difficulty that must 
be reckoned with always. In fact a student's first lesson is the show- 
ing of an artificial tooth before fusing and after, and it never fails to 
create surprise and comment and is a simple object lesson that im- 
presses. Shrinkage of porcelain is always a fifth of its bulk, some- 
times quite one-fourth. In small matrices it cannot make much 
change, but in proportion to the size and quantity do the diffi- 
culties increase. It may draw from the walls of the matrix and form 
crevices at those parts, or it may shrink and draw the form with it, 
and to avoid this my favorite way is to mix small particles of broken 
porcelain with the paste. Another way is to cut grooves or concaves 
at its greatest bulk which divides the material and avoids the crevicing 
to some extent. The main desire is to have a shrinkage that will 
change the form of the matrix the least, and some porcelains have a 
value in this respect. An invested matrix is more secure, but it has 
drawbacks that in my estimation are often detrimental. A matrix 
for investment must be intact at every point which is possible with 
gold, but not always so with platinum. Once invested it must be 
completed in that form thus debarring opportunities for trial or re- 
burnish, added to which are the increased difficulties of getting proper 
form or contour while invested. 

FUSING. 

This is the coherence into a solid mass of the various substances 
which constitute porcelain and it is this cohesiveness which causes 
shrinkage, and because of this shrinkage repeated firing is imperative 
to obtain the necessary bulk of solidified material. It may be twice, 
three times or more according to the extensiveness of the operation, 
therefore a knowledge of fusing is an important part of making an 
inlay, and one that necessitates considerable experience. Of course 
results are obtained without exparience or much practice, but these 



28a THE PORCELAIN INLAY. 

results arc not always properly fused porcelain. To illustrate this 
point let me state that a certain dealer and manufacturer wishing to 
impress upon the profession the advantages of a pyrometer attachment 
molded small pellets of porcelain of equal size and of one color and 
mailed them to "porcelain workers" in various parts of the country, 
asking them to fuse and return. I was so favored with this request, 
but did not know the results for some months afterwards when by 
chance I saw the "returns" mounted on a card for exhibition pur- 
poses and the various shades and qualities produced by that one little 
pellet was a revelation. They were all supposed to be correctly fired 
and no doubt each participant in this trial thought his specimen a 
correct one. This shows in a simple manner why there is so much 
demand for information regarding shading, which demand can be 
lessened by greater knowledge of fusing. How can this knowledge 
be obtained in the most practical manner? By studying the various 
degrees of heat with the eye which may be aided by a watch or a 
pyrometer, but with either of these or any other guide the correct 
fusing or baking of porcelain reduces the problem to one of per- 
sonal equation. 

A pellet of gold is recommended by many to assist in determining 
the fusing points. The gold is placed in the muffle near the inlay 
and its melting denotes the fact that a certain temperature is reached, 
and so much time by the watch is allowed between the melting of the 
gold until the fusing of the porcelain. The time to allow is learned 
by repeated firings, but various sizes of porcelain being baked at the 
same time must be guessed at. 

The use of a pyrometer in connection with a furnace is accepted 
by many as being the most scientific solution of our fusing troubles, 
and there is no doubt that it is of much assistance to the majority, 
but it is a machine and therefore it has no judgment and fusing 
porcelain requires that necessity. Concentration of a thousand heat 
units for twenty minutes will produce certain results and the same 
condition will be obtained by increasing the volume and reducing the 
time, and as we are fusing irregular quantities, either the heat or 
fusing point must be varied because these fusing points now used as 
a standard were obtained by baking porcelain pellets of uniform size 
at a regular heat for a certain time with the rheostat on a positive 
point. These facts, therefore, must place the pyrometer in the position 
it should occupy and that it is a guide which will indicate the furnace 
heat and not properly tell when the fusing has taken place. The man 
who uses his eye as a guide can fuse any material under all circum- 



FUSING. 283 

stances and feel that he has control of the situation, providing he uses 
an article which fuses at 2300 ° or less. Over that point it is a greater 
strain on the eyes and the value of a pyrometer is correspondingly 
increased, but the proportion of operators using such excessive heat 
for inlays is very small. 

The operator after some practice will observe that various degrees 
of heat have a shade indicative of the point he desires. The first 
will be a deep orange color which will fuse a low porcelain body ranging 
from 1500 F. to 1800 F. If an electric furnace is being used, ad- 
vancing the rheostat to the next point will increase the brightness of 
the muffle to a yellow, giving a fusing temperature ranging to 2100 , 
and another step higher a bright yellow appearance, and a heat 
sufficient to fuse most of the "high fusing" bodies or those ranging 
in the neighborhood of 2300 °. Beyond this point there is a glare 
that may be injurious to the eyes unless protected by smoked glasses. 

Dr. Hart J. Goslee, in a recent article on this subject makes a 
valuable suggestion that I take the liberty of quoting. "A degree of 
familiarity with the physical change which takes place during vitrifi- 
cation and which will enable one to thus detect the proper fusion, 
may be easily required by the continued fusing of small cubes of 
properly mixed 'body' placed upon the labial surface of a central 
incisor facing until he can distinguish between the granular surface 
of the 'body' and the glazed surface of the facing and observe when 
the surface of the former becomes the same as that of the latter." 

The "first fusing" is carrying the inlay through these various 
stages of heat until it arrives at what is usually termed a "biscuit 
bake." This is a reduction of the different ingredients to a solid 
vitrified mass without a gloss. Drawing it from the furnace in this 
condition and exposing it to the air does it no injury, in fact small 
work even when finished does not require particular care in this 
respect, but large sections and crowms should be immediately placed 
in a cooling muffle until cool enough to handle. 

After the first bake the surplus platinum is trimmed and the inlay 
adjusted in the cavity. The removal of excess matrix material insures 
easier access to its position and allows a better observance of general 
contour. The flat blade of a burnisher is pressed along the edges 
until the matrix sets firmly in position and that part of the matrix 
which may have been changed by the shrinkage is forced back to the 
cavity walls. The inlay is again removed and body added, first 
cleaning off the surface with a brush, being careful to have any crevice 
thoroughly filled w r ith porcelain, thereby preventing little air holes 



J 84 THE PORCELAIN INLAY. 

which sometimes defy eonsiderable tapping. The inlay is again 
given the same considerations as at first baking, but watched with 
greater care when the heat is nearing the fusing point, because in- 
sufficiency of heat will not produce the true shade or finished surface, 
while too much heat will make it lighter in proportion to the exces- 
sive heat beyond the exact point, and reduce the quality of the material. 

Better results will be obtained by withdrawing the inlay before 
it is thoroughly fused and note the condition particularly in regard 
to amount of material, for if another layer of porcelain is required 
to give it the proper contour or to have the inlay level with the margins 
of the matrix, it is better to make this addition at this time, and in so 
doing the whole mass will be more homogeneous with a truer shade 
if the final heat is correctly gauged. 

If the inlay is satisfactory to the operator the next step is to strip 
the matrix, which is done with fine straight pointed tweezers, catching 
the outer edge and turning backwards toward the middle which will 
avoid chipping the edges. Very frequently small pieces of the metal 
adhere very persistently to sections of the porcelain. These may not 
be of disadvantage in large inlays, but in small ones the shade might 
be affected, therefore it is recommended that every portion be removed, 
and an old bur will do this easily. My usual procedure after stripping 
the matrix is to place the inlay in the cavity, always wet, which brings 
out the shade and adds life to it, and it is at this point the new porcelain 
worker has his first desire for a transparent cement. It is now that 
the patient is invited to view it for he is usually as interested as the 
dentist, and it is also good policy to explain the probable change that 
will take place by the drying of the tooth and the cementation. This 
change is often temporary though sometimes permanent, much to 
our disappointment, but experience may help to reduce it to the 
minimum. 

The inlay must now be prepared for retention. There are three 
important factors toward permanency, first, shape, which is given 
by due consideration of cavity preparation, second, the undercutting 
or serration of the porcelain, and third, the quality of cement. Many 
failures can be attributed to concentration on the latter, ignoring the 
importance of the first two requisites. Careful attention should be 
given to the inlay itself, large or small, thereby saving time, discomfort 
and reputation. My preference is undercutting or grooving when 
possible, but that is not always practicable, so it may be necessary to 
etch the cavity side of the inlay with hydrofluoric acid which has a 
powerful chemical affinity for all vitrified surfaces, destroying the 



FUSING. 285 

gloss and allowing a better union with the cement. Almost the same 
results are obtained by using small carborundum or corundum 
stones, and many follow this method exclusively, while others use both 
roughening and grooving. 

The disks employed are diamond, hard rubber and corundum or 
carborundum. The diamond disks are expensive and unless used 
carefully very soon lose their efficiency. The cheaper disks cut 
quickly and with moderate care are durable. An objection to car- 
borundum is its brittleness, and the fine black dust that lodges in the 
porcelain and is not always easy to eradicate. The groove should 
be made on at least two sides and more if possible. In using acid 
care must be taken to keep the finished surface intact and this is done 
by making a block of beeswax about one inch square, soften a surface 
over a flame and sink the inlay face down using a warm spatula to 
cover edges. Drop a little acid on the exposed surface and leave it 
for five to eight minutes, wash off with water and put the inlay in 
alcohol which will loosen a fine scale which is scraped off with an 
excavator. If this surface is not removed the cement will not get 
a true attachment. No matter how the inlay is prepared it should 
be thoroughly cleaned with alcohol. The mouth is now put in readi- 
ness for the final adjustment of the inlay. Thorough dryness is an 
important essential, and for this purpose probably the rubber dam is 
the most efficacious, although if one is accustomed to the proper use of 
napkins, the unpleasantness of the dam can be avoided in the majority 
of cases. The cement is mixed to a creamy consistency and applied 
to the' cavity with a spatula and the inlay inserted immediately, forcing 
it to position by gentle pressure, holding it there until crystallization 
has commenced. If the inlay is of a simple character further direc- 
tions are unnecessary, but if complex and extending to the incisal or 
occlusal surface material assistance is obtained by a soft wooden 
wedge such as a tooth pick, or waxed floss silk wound about the tooth. 
A tape floss silk is advantageous because the broader surface equalizes 
the pressure and as it is drawn over the joints it removes excess cement 
and exposes the union, showing at a glance if the porcelain has its 
correct position. When it is not convenient to do this use small 
squares of spunk, which is soft and firm, for the removal of excess 
cement while it is soft has a distinct advantage. 

After the cement has set and before removal of dam or napkin 
cover the operation with some moisture preventative such as sandarac 
or rubber varnish, chlora-percha or paraffin wax. The last men- 
tioned is preferable because it is not disfiguring and gives a blending 



286 THE PORCELAIN INLAY. 

effect to the porcelain and tooth and will remain a sufficient time 
for the purpose desired. The inlay may be finished in an hour or at 
some future sitting for there is always some finishing with the most 
perfect work. It may be only a slight disking or it may be that edges 
need a stone. If so use a small narrow edge of fine grit, grinding no 
more off the glossed surface than positively necessary, although at 
times the occlusion is such that the surface must be defaced. After 
grinding, the surface should be polished, smoothness being the main 
object. 

PORCELAIN SECTION ATTACHMENT. 

When it is possible to use an all-porcelain anchorage in restoring 
a section of a tooth, that method is preferable, because the whole 
mass of material is of one substance, thereby rendering greater resis- 
tance to leverage; but occasionally we must resort to other means of 
retention, and the use of platinum wire pins, loops, or staples is rec- 
ommended. 

Pins from old porcelain teeth can be used without any other prepara- 
tion, but they are too thick and rarely indicated in preference to the 
loop or staple, the latter being adapted to almost every purpose and 
being also easier to manipulate. Directions for their use are few 
and easily followed. The tooth is prepared as directed on previous 
pages, and a platinum matrix made of the edges and cavity, the thick- 
ness the same as in other inlay work excepting for the cross- section 



Fig. 258. Fig. 259. Fig. 260. 

of a tooth, when it can be slightly heavier. The wire being the an- 
chorage, it is unnecessary to cover the floor of the cavity with platinum, 
therefore breaking the matrix is expected. This being done, take 
iridio-platinum wire gauge 24 and bend in staple form to fit. 

Figs. 258 and 259 give the idea of wire formation for a majority of 
cases, while that shown in Fig. 260 is probably more desirable where 
there is extreme sensitiveness, it being easier to place retention holes 
for wire ends than to cut across the tooth to accommodate the loop. 
The staple with points in the porcelain is stronger, however, than that 
with the points in the tooth. The attachment to the tooth may be 
equal in strength, but the tip or corner or any section of the porcelain 
having the least foreign material must be the stronger, hence the 



PORCELAIN SECTION ATTACHMENT. 287 

argument in favor of an all-porcelain attachment when that is possible. 
The weak points of the porcelain shown in Fig. 261 are opposite to the 
ends of the wire, while the weak point of that shown in Fig. 262 is as 
far as the loop extends, although this weakness will be less in pro- 
portion to thickness of the porcelain. 

While the matrix is in position, the wire is inserted and held there 
with paste porcelain made of water and gum tragacanth or mixing 
fluid. Absorb moisture with bibulous paper or spunk and then gently 



mm 

Fig. 261. Fig. 262. Fig. 263. 

withdraw the combination from the tooth, and after carefully drying 
at the mouth of the furnace fuse it the same as other work. 

These few simple directions will save the time and trouble nec- 
essary for soldering the staple and matrix together, and will also insure 
a purity of porcelain not otherwise possible. 

Fig. 263 shows the loops or pins attached in the porcelain and ready 
for trial, reburnishing the edges and finishing as represented by Figs. 
264 to 267. 

Fig. 268 is a part section of a bicuspid showing a way of restoring 
that is most satisfactory. I have made many such cases, and have 
yet to learn of the first failure. A whole crown is no doubt quite as 
easy to make, but at times a demand for the least loss of tooth makes 
such a repair desirable. 







Fig. 266. Fig. 267 Fig 



The building of tips and corners can be more quickly accom- 
plished by using pieces of broken porcelain tooth in the foundation, 
thus allowing a high heat without change in the prominent contour. 

About five years ago a firm in London introduced small wedges 
of porcelain called "Mellersh Cores," their name being taken from 
that of the inventor. They are in various shades and will take a high 
heat without change of form or color, and can therefore be used to 
advantage in contour work. 



288 THE PORCELAIN INLAY. 

CEMENT. 

It is generally conceded by porcelain operators that while a material 
oi this kind is almost an ideal filling, it falls short of the ideal because 
we are forced to use as an attachment a substance detrimental to the 
aim which we have in view, namely, the absolutely invisible restoration 
of tooth form. Though approximating the ideal we can never fully 
reach it while we have to depend upon an opaque substance as a means 
of retention. Still the many good qualities of cement will insure its use 
for many years to come, for even if an ideal cement should be dis- 
covered it will take time to establish a confidence equal to what we 
now have in the material at present in use. The question may arise 
as to what is an ideal cement. In many cases what we are now using 
is ideal, that is from a tooth saving viewpoint, but its failure is that 
it does not save itself. Cement saves the tooth and porcelain protects 
the cement, thus making a combination which but for esthetic reasons 
would be almost perfect. Translucency and perfect color matter 
little in some instances, but in others they are highly important and the 
profession should hail the advent of a material having all the necessary 
qualities as the fruition of a long desire. 

Porcelain inlays can be made perfect in shade and shape and the 
texture may approximate tooth substance in a highly satisfactory 
manner, but immediately upon attaching it permanently the shade is 
changed through the difference between the three substances, all of 
different density, coming in close contact, namely, porcelain, cement, 
and tooth. The cement being the chief point of difficulty, it is im- 
portant that the objectionable features should be reduced to the 
minimum. 

It is a poor cement that is not at least a preventative. Many 
resemble each other in manipulative qualities with the difference 
of slow, medium and quick setting tendencies. Some are coarse and 
others are fine and a few have a combination of many good qualities, 
but with that tendency to "pack" under pressure which causes annoy- 
ance to porcelain workers. A cement closely ground of clear color 
and medium to slow setting, having the maximum adhesiveness with 
the least amount of powder is what is recommended for a successful 
operation. In addition to this, it should have the greatest amount of 
resistance to moisture during what is usually called the "setting" 
period. 

Shading a cement to match the tooth, or to lighten or darken either the 
porcelain or tooth or both is quite troublesome, and, at times, disappoint- 
ing. It is of considerable assistance to mix pellets of cement of various 



CEMENT. 289 

shades and mount them on a card. This allows of comparison and 
saves much time and guesswork. Yellows are the most required, and this 
is fortunate because pure calcined oxide of zinc is yellow, ranging in 
degree of shade from a canary color to cream white, and its chemical 
combination with phosphoric acid is more complete than when other- 
wise changed. The variations in shade depend upon the product 
and it is conceded that the best quality of zinc oxide comes from 
France. This is of the lightest shade, but it is not safe to assume that 
the light shades are all of this origin, because manufacturers sometimes 
produce these variations by coloring matter which has a deteriorating 
tendency. It may be infinitesimal in blues and grays, but white is 
made so by oxides of aluminum or zinc which reduce the chemical 
union of the powder and acid in a marked degree. All phosphate 
of zinc cements are similar in manufacture and much the same results 
are obtained, although some are better adapted than others to use in 
connection with inlays. 

Some inlay troubles are caused by injudicious selection of cements, 
that is using a quick setting cement instead of a slow one, or vice 
versa. Another factor is improper mixing in the way of insufficient 
spatulating which gives poor results through non-incorporation of the 
two ingredients. Cement mixed too thin will not have the body of 
material required for resistance, with the added danger of displace- 
ment during the longer period which it takes for setting. Cement 
mixed too thick prevents proper seating of the porcelain and a close 
union, with probability of fractured edges through endeavors to force 
it to place. Quick setting cements should be avoided in complicated 
conditions. Slow setting cement has less value on corners and tips, 
for usually such places have free- access and a quicker setting cement 
will reduce the possibility of displacement, which is increased through 
prominence. 

In the past four years much attention has been given to the new 
silicate cements which are on the market under various names with 
many impossible recommendations, therefore a word on this point 
may be of some interest particularly in connection with porcelain inlays. 
These .cements are nearly all produced in Germany and it has been 
my fortune to be familiar with this material almost from its origin, and 
in that time have formed conclusions through actual observations 
that may be useful. These silicate cements have not that perfection 
claimed by the manufacturers and agents, but they have reached a 
stage wherein it is safe to prophesy an ultimate success, how soon, 
it is not possible to say. That they meet all. requirements at present 
19 



JOO THE PORCELAIN INLAY. 

or that they can take the place of porcelain is not worth argument, 
but as an attachment they come nearer to the ideal in appearance than 
anything yet produced. Their strength and adhesiveness to tooth 
structure cannot be compared with the ordinary phosphate of zinc 
cement. 

In mixing a silicate cement one is impressed with its tenacity to 
smooth surfaces, leading to the belief that it must be particularly applic- 
able to porcelain restorations, but in many practical tests it is found 
that after a few months this adhesiveness has decreased and the filling 
is easily dislodged. This being the case its use as a medium for inlay 
attachment is somewhat hazardous. It has a value because of shade 
and its resistance to "washing out," but this is counterbalanced 
by crevicing and fracturing and changing appearance in many mouths. 
And yet there are instances where this material wears well and after three 
years has almost the appearance of porcelain, but these cases are rare. 

SHADING. 

The color problem in connection with inlay work is one of much 
inquiry and discussion. It is a phase of the work most perplexing 
and the rules given by some authorities are both diversified and 
difficult, requiring close attention even by the most experienced and 
often proving discouraging to the beginner. The size and position 
of an inlay will govern shade to such an extent that consideration of 
this fact is one of the first rules. The application of the shade guide 
to the tooth may lead to an incorrect conclusion, because quantity 
of material adds depth to the shade and most of the guides are pointed. 
Frequently the point is placed against the tooth without allowing the 
eye to take in the whole size and general effect. Thus when the inlay 
is finished it is found to have a lighter appearance which is an error 
not readily rectified. Overfusing is probably the cause of more 
poorly shaded inlays than wrong choosing of shade, therefore the 
choice of something slightly darker is recommended particularly 
if the operator has limited experience. A rule which can be applied 
more frequently to a simple labial inlay is to choose a shade darker 
and reverse the order when applied to small proximal cases. Some- 
thing darker between the teeth will surely cause a shadow which can 
be avoided by lighter shades. The cement which is the background 
is an opaque substance and is therefore a strong factor and one that 
must not be overlooked, but even with this consideration in mind the 
most beautifully shaded work is sometimes disappointing. In many 
cases, however, this is corrected to some extent by time. 



SHADING. 291 

In larger inlays and sections of porcelain the cement interference 
is reduced by being overcome with volume of material and stronger 
basal shade body which is toned to the desired shade by lighter tints. 

Various degrees of yellow are used as foundation shades in the 
majority of cases with the possible exception of pulpless teeth. These 
teeth having decreased translucency the opacity of a solid mass is 
not so noticeable and the question devolves to one of matching alone. 
And yet the shading of such a tooth requires considerable artistic 
skill because the operator must do the blending to suit the various 
shade conditions present and which are not to be found on any one 
shade guide. ' 

Take, for instance, a large incisal contour embracing one-fourth 
of the tooth with pulp alive, and the shades may vary from a deep 
yellow near the gum to a light yellowish-blue at the incisal. This 
would be matched up with three shades, which are all listed and ready 
for the mixing; but if pulpless the neck portion might be a brown 
with a greenish-blue center and a lighter hue at the edge, thus showing 
that considerable mixing must be done which means guesswork in 
many cases. The artistic porcelain manipulator is handicapped when 
compared with a painter w,ho has his palette and colors and desires 
certain difficult combinations to portray what he sees or is in his 
mind's eye. He mixes and sees immediate results, whereas with 
porcelain the shades are powders with no color guidance until the mass 
is reduced to a vitreous substance, and then not correctly so unless 
the artistic sense is carried to a completion. A great quantity of 
matter has been written and published in regard to the proper way to 
shade porcelain and many excellent rules are formulated, which if they 
could be carried to a successful issue at all times would reduce this 
problem to perfection, but rules and directions are of little value 
without artistic skill to carry them out. This cannot be bought 
although it may be acquired to some extent, and yet it must be inate 
in the same ratio that mechanics are part and parcel of the successful 
dentist. Rules may assist but they cannot always be practical. It is 
claimed that the most successful mode of shading is to build the inlay 
by layers of different enamel shades which "break up the absorption 
and refraction of light rays," thereby giving an opalescence to the 
inlay not to be obtained otherwise. This is excellent practice and 
cannot be criticised when circumstances favor this procedure, but there 
are times when the blending of shades will give equal if not better 
results and the simplicity of blending is much easier grasped by the 
inexperienced. Outside of this is the fact that with one exception 



292 THE PORCELAIN INLAY. 

all inlay materials are made for blending and the thousands of beauti- 
fully matched inlays made with these materials must prove the fact 
that merit is not limited to the layer method alone. 

Dr. W. T. Reeves originated this method and to him we owe 
much valuable literature on this subject, therefore it will be of interest 
to reprint what is claimed by him can be accomplished by observing 
these three rules. 

" First. A neutral translucent-looking inlay. Put colors on strong 
enough, that when covered with what might be called an enamel 
layer will allow the colors to reflect through, the enamel layer modify- 
ing and harmonizing the colors. This will gi\ie the translucent effect 
so desirable. 

" Second. If built of three or more layers of different bodies it will 
break up the absorption and refraction of light rays, so that from 
whatever angle or point of view looked at it, it will appear practically 
the same. An inlay built all of one body or mixture will absorb light 
only from one direction, and viewed from one point will look all right, 
but from the opposite point of view will show as differently as black 
and white. An inlay in layers will come very near imitating nature's 
method of building up a tooth and by breaking up the direct absorp- 
tion and refraction of light rays, will come very nearly looking the 
same from all points of view. 

"Third. You overcome that great bugbear of most inlay workers, 
the cement showing through after the inlay is set. An inlay built 
up in layers will almost overcome the reflection of the cement through 
from underneath. You will often hear operators say they had a 
splendid color before the inlay was set, but after it was set the cement 
killed it entirely. That was because the inlay was baked all of one 
body and the cement could reflect through from underneath as easily 
as the light was absorbed only in one direction from above. The 
three points I claim for this method are translucency, avoidance 
of shadow, and prevention of cement reflection from underneath." 

PORCELAIN BODIES. 

Until recent years the advancement of porcelain operations was 
much retarded because of few and unsuitable materials, but now the 
variety is almost bewildering. In fact it is a question if the market 
is not overdone in this respect. 

There can be no objection to every porcelain operator having a 
varied stock of porcelain, provided his experience has been sufficient 
to enable a skillful discernment of the various qualities of each, and 



PORCELAIN BODIES. 293 

thereby produce gratifying results by eliminating those of lesser 
merit until he has secured what in his hands will give the best basis 
for general application, but the beginner is likely to be confused by 
so many different makes. 

The value of a product in the eyes of many is the assortment of 
shades. This of course is natural if the operator has had little ex- 
perience, bujt as he becomes more skillful he finds that at least half 
the number is sufficient because he has learned that a little manipula- 
tion of a certain few will give the same results in the majority of cases. 
This statement will be better appreciated by those who have had to 
contend with the earlier condition of affairs, when only a few stronger 
shades were available, and they will also agree that an ideal shade 
guide could be limited to a dozen and then readily cover all require- 
ments. The porcelain inlay worker of eighteen or twenty years ago, 
had much to contend with and many discouragements to overcome, 
and much of the antipathy to this new branch of dentistry was no 
doubt caused by the crude appearance of many so-called finished 
operations, some of which were far from esthetic whilst those having 
that recommendation were cases fortunate enough to be within the 
range of two or three varieties of continuous gum bodies such as 
Allen's, Tee's and Close's. These gave a few shades of yellows 
which were regulated to a great extent by heat, therefore a tooth with 
gray or blue tints to be matched up with yellow meant a discrepancy 
of shade which justified much criticism. Subsequent events have 
proven that these efforts had merits because they resulted in different 
manufacturers putting various porcelain bodies on the market, with 
a larger number of shades and varying degrees of fusing point. 

Porcelain work was increasing rapidly in the latter part of the 
nineties and in 1898 received a gratifying impetus by the introduction 
of Dr. Jenkins' low fusing enamels with an outfit particularly designed 
for using this material with a gold matrix, for up to this time platinum 
was used exclusively for that purpose. The advent of these goods 
and the process of using them was the origin of the controversy still 
existing in regard to the superior virtues of low fusing porcelain over 
the older and longer tried high fusing. This question has been debated 
in public scores of times and it is still unsettled, although the differ- 
ences of opinions are not so positive, for adherents of both factions 
are forced to admit that each have certain advantages, which when 
properly recognized lead to the ultimate gain of the work. The 
introduction of Brewsters' material was an advanced step for the cause 
of high fusing porcelain and he was the first and only one to give us 



J 04 THE PORCELAIN INLAY. 

enamels with basal shades, thereby increasing the possibilities of 
translucency which was lacking in many products. 

During the past five years the S. S. White Dental Co. have done 
much toward the advancement of porcelain, having introduced a 
variety of shades at various fusing points. The Consolidated Dental 
Co. have also a splendid assortment with a fusing point sufficient to 
satisfy the most enthusiastic advocate of high temperature. Johnson 
and Lund's goods are of the best quality and the fusing point is also 
high. It is generally conceded that a fusing point of 2200 or 2300 ° 
is sufficiently high and quite suited to inlay purposes and the increased 
strain on the electric muffle and the extra time required for such heat 
counterbalanced the small advantage of an extreme heat if such exists. 
The following goods having been thoroughly tested can be considered 
of a standard quality and the assortment is varied enough to suit any 
demand. 

Whiteley's 19 shades fusing about 2300 

S. S. White Dental Co., 26 shades fusing about 2300 

Brewsters Dental Co., 9 shades foundation body 2300 

Brewsters Dental Co., 24 shades enamel 2160 

Brewsters Dental Co., 10 shades (gold matrix) 1820 

Brewsters Dental Co.. 18 shades (gold matrix) 155°° 

Jenkins Dental Co., 18 shades (gold matrix) I 55°° 

Consolidated Dental Co., 23 shade 2600 

Johnson and Lund, 25 shades 2 55°° 

Ash and Son, 7 shades 1900 

FURNACES. 

Porcelain as applied to dentistry at the present time has assumed 
such importance that it is difficult to conceive of the fact that only 
twenty years has elapsed since the invention of the first furnace which 
reduced the time of fusing small pieces of porcelain to a matter of a 
few minutes, and to this fact we owe the real birth of that branch of 
dentistry which is generally conceded to be a distinct advancement. 
There is no doubt that tooth carvers and continuous gum workers of 
many years back have had visions of what the present generation 
enjoys by the adaptation of this esthetic work, and they have given 
much thought toward the solution of the fusing problem, for that was 
the obstacle first to be overcome, having recognized the futility of 
much advancement while harnessed to the cumbersome and slow coke 
furnace. 

The quality of workmanship produced in this manner is beyond our 
criticism which proves that improvements in that direction were not 
required, but toward reduction of time and convenience so that small 
work could be possible and with little preparation. 



FURNACES. 



29: 



To Dr. C. H. Land, of Detroit, belongs the honor of being the 
inventor of the first small furnace distinctly different from any other 
and especially adapted for this work, in which he takes such an im- 
portant position in its history. Much praise must be accorded him 
for his persistent efforts and inventive genius. 

This furnace was called a "Compound Gas or Gasoline Furnace" 




Fig. 269. 



and was first described to the dental public in Items 0} Interest, Oct., 
1886, under the heading tk Are Hydro-carbon or Gas Furnaces a 
Success?" (Fig. 269.) 

These furnaces were lined with fire clay with a muffle of the same 
material. The air blast was supplied by a foot bellows and took 
about thirty minutes' continuous pumping to secure the necessary 
heat. The results were not always satisfactory, as frequently the gas 



2 00 



THE PORCELAIN INLAY. 



was forced through the muffle causing 



which was a diffi- 



culty to be contended with in using any gas furnace. 

Four years later the same inventor produced a smaller furnace of 
the same kind which was called "The Midget Blast Furnace" and 
was a decided advance because the muffle was much smaller and 
made of platinum, thus allowing quicker heating and reducing the 
"gassing," tendency, (see Fig. 270). These little furnaces could be 
heated sufficiently to fuse the highest grade material in seven to ten 

minutes and have been a decided 
favorite over all others of the same 
kind, and there are many still in 
use at the present time. In fact, 
the w T riter did not discard his 
until eight years ago, because its 
efficiency was in marked contrast 
to the troubles of the more modern 
electric. These troubles have been 
reduced to some extent, but entire 
elimination must not be expected. 
In the early nineties several 
gas furnaces were marketed, the 
most notable ones being Parker- 
Stoddart, Fletcher, and Downie. 

The application of electricity 
to dental appliances became gen- 
eral in the early nineties and when 
Dr. L. E. Custer invented the first 
practical electric furnace in 1894 
the improvement was considered 
to be a marked advancement, be- 
cause heretofore the fusing of por- 
celain by means of gas meant labor 
to produce the blast w r hich with its attendant noise was most undesir- 
able. Electricity eliminated the possibility of "gassing" the porcelain, 
a trouble which cannot be understood unless experienced and one 
which added much to the discouragement of the early porcelain 
workers. This new furnace being absolutely noiseless and clean was 
an addition to the operating room and thereby a convenience much 
appreciated. Its form was adapted more to the use of continuous gum 
work and is shown in Fig. 271. 

It is practically unchanged at the present time, the only improve- 




Fig. 270. 



FURNACES. 



297 



ment being in the heat regulation and easier repair necessitated by 
wires " burning out." In fact the trend of improvement in all dental 
furnaces from this date forward has been mainly toward the reduction 
of this trouble. 

Two years after this first electric furnace, or in 1896, the Detroit 
Dental Mfg. Co. marketed the "Downie" which differed from the 
former mainly in general form of the furnace and the mode of wiring 
the muffle. 




Fig. 271. 

The next furnace brought to our attention was a very small one 
invented by Dr. Mitchell, of London, and intended for low fusing bodies 
as it was practically useless for anything higher than Ash and Son low 
fusing porcelain. In 1899 an d 1900 there were three more, viz., 
Hammond, Peck and Gerhardt, then the Pelton in 1902 and Price's 
in 1903. 

The most recent addition to a numerous list is Roach's Auto- 
matic and Caulkins' "Revelation" in 1905. The Hammond had a 
valuable distinction from all others from the fact that in case of wires 
burning a new muffle could be substituted immediately. This im- 



298 



THE PORCELAIN INLAY. 



provemcnt was a decided advantage and other manufacturers soon 
made the same arrangement. The Price was introduced to the pro- 
fession with a pyrometer attached, and this improvement has resulted 
in all the leading furnace manufacturers at the present time having a 
pyrometer attachment in some form or other. There is very little 
difference in the merit of these various furnaces, therefore the intend- 
ing purchaser cannot be far astray in a choice of any one mentioned, 
although it is important to consider the amount of heat developed on 
the first step of the rheostat if the dentist is using low fusing material, 
as several furnaces develop a heat at that point great enough to destroy 
that material unless watched very intently. 

For many years porcelain oper- 
ations were confined to those for- 
tunate in having electricity or gas 
conveniences, relegating the practi- 
tioner without these advantages to 
the rear of the vanguard of dental 
progress. This may not have been 
a hardship to the majority, because 
in small places the demand for por- 
celain work is always limited, but 
there are many dentists ambitious 
to do all kinds of work, therefore 
the introduction of the gasoline 
dental furnace by the Turner Brass 
Works, of Chicago, in 1900, was a 
decided step toward the advance- 
ment and equalization of the pro- 
fession at large. The furnace is 
simple of construction and capable 
of producing a heat sufficient to fuse any porcelain and will do it 
quickly and safely. 

This apparatus with the accompanying soldering appliances 
enables the rural dentist to be an up-to-date practitioner and the 
numerous sales of this furnace is a testimony that this fact is appre- 
ciated. 

There is also another gasoline furnace called the Brophy, which 
is similar in construction and has equal merit with the original. In 
conclusion it is apropos to state the fact that improvements in appli- 
ances for the purpose of fusing small quantities of porcelain quicker 
was applied on a larger scale to the manufacturing of teeth with the 




Fig. 272. — Lewellan furnace. 



FURNACES. 299 

result that the old fashioned coke ovens are now obsolete, having been 
replaced with the more modern oil burners, which are quicker, cleaner 
and save much labor. 

They are an improvement and an enlargement of one made for 
continuous gum by Dr. C. H. Land, in 1892. The simplicity of its 
form and amount of high heat produced was one of wonderment to 
the profession at that time. 

The fuel is the regular refined petroleum or "coal oil" syphoned 
to a burner at the base of the furnace, which is so constructed that a 
natural draught is all sufficient to produce the highest heat required 
to fuse any porcelain body. They are absolutely without noise or 
odor and very economical and highly satisfactory in smaller sizes for 
continuous gum work, but they can only be used where there is a 
chimney which is necessary for the draught. (Fig. 272.) 

To Mr. Lewelan, of Philadelphia, must be credited the improve- 
ments of this furnace which has revolutionized the mode of fusing 
large quantities of porcelain. 



CHAPTER XVII. 
CONSTRUCTION OF GOLD INLAYS. 

JOHN EGBERT NYMAN, D. D. S. 

Recently the construction of gold inlays has been entirely revolution- 
ized. A method has been devised by Dr. W. H. Taggart, of Chicago, 
which supplants all other methods. Applicable alike to simple 
and to complicated cavities in any situation, obtaining readily any 
desired proximal contour and occlusion, and with uniform certainty 
of absolutely accurate results, it may well be styled "the best" method 
of gold inlay processes. 

It embodies all the factors that are requisite of any method that 
maybe termed " ideal, " such as accuracy and permanency of results, 
comfort of patient and operator, ease of manipulation, economy of 
time. 

It is essentially a method of accurate casting of gold inlays, some- 
thing heretofore impossible, but now easily accomplished by means 
of a marvelously ingenious device for the application of gas pressure to 
molten gold. One of the essential problems in this process of casting 
inlays, which had to be solved was the obtaining of a mold which 
should have no joints or crevices about it; this necessitated a model 
of the inlay desired, that could be dissipated completely without 
residue, by some means which would not in any way injure the mold. 

Dr. Taggart finally succeeded in producing a wax of which a 
model inlay could be made in the cavity of the tooth, carving it to 
the desired contour, proximal and occlusal. It was essential that the 
wax become plastic at a temperature that could be tolerated by the 
tooth, that it would not shrink or warp in cooling, that when cool it 
would be so hard that it could be removed without distortion, but 
would not be so brittle as to crumble under the carving instrument, 
that it could be vaporized by heat. All these essentials were finally 
obtained. 

Then there was the problem of the mold. Of what should- it be 
composed and how constructed? It was essential that the mold 
material withstand a temperature of at least 2100 F. or 1170 C. 
(slightly above the melting point of pure gold) without shrinking, 
cracking or softening; that it should be finer in texture than any invest- 

301 



302 CONSTRUCTION OF GOLD INLAYS. 

ment material with which we were then familiar; that it must present 
an absolutely smooth surface in the mold cavity; that it should set 
sufficiently hard to permit of manipulation without crumbling. This 
was finally obtained by a combination of silex magnesia and plaster. 

These two factors having been obtained, there still remained to be 
devised some method of forcing the molten gold into the mold so that it 
would fill the mold to the uttermost corner, a rather difficult problem 
considering the strong tendency of gold to "spheroid", as it is tech- 
nically termed, or "ball up" when in a molten or fluid condition. 

The genius of Dr. Taggart which had solved two of the problems 
proved fully equal to the third, and at last after months and months of 
experimenting with nothing to aid him but his own inventive ability, 
his masterly knowledge of physics and mechanics, and his faith that he 
would at last succeed, he did succeed in constructing a machine that 
would accomplish all that was to be accomplished and so complete was 
his success, that it was absolutely startling to the profession, creating a 
sensation such as had never before been known. 

It is no exaggeration to state that in the history of the profession 
nothing to equal this process in value has ever been given it. 

The method is as follows : The cavity having been prepared, a mass 
of the special wax (which is dark green in color in order that the slightest 
overlap on the surface of the tooth may be readily noticed) sufficiently 
large to more than fill the cavity is softened by immersion for about 
five minutes in water of a temperature of from i35°-i4o° F. 
or 77 C. This softening must be done carefully and the wax must 
not be manipulated until it is softened through and through. If 
insufficient heat is used the wax will crack when it is forced into the 
cavity. If too much heat is used the surface of it will become pasty 
and will crumble when an attempt is made to carve it. To soften it in 
or over a flame must never be attempted as the surface will flow and 
then become pasty while the interior mass remains too hard to be 
manipulated. Until one becomes familiar with this softening process, 
it will be best to use a thermometer to determine when the proper heat 
(140 F.) has been obtained. While the wax is softening, let the 
patient hold water as hot as can be tolerated in the mouth in the 
vicinity of the cavity so that the tooth will not chill the wax too quickly 
when it is inserted in the cavity. 

The mass of wax first softened should be shaped up by the fingers 
so that it will approximately fit the cavity, then the partially shaped 
mass is softened again and pressed into the cavity; this will insure its 
being forced into every corner of the cavity without cracking. 



CONSTRUCTION OF GOLD INLAYS. 



303 



The wax is inserted into the cavity (which must be moist), pressing 
it in with the finger tips rather than with an instrument. 

The patient is at once instructed to bite into it and to chew upon 
it. It is then hardened by chilling it with a stream of cold water or 
having the patient fill his mouth with cold water for a few minutes, 




Fig. 273. — Instruments for trimming and carving wax fillings for gold inlays. 
1. For occlusal surfaces. 2, 3, 4, 5, 6. For proximal surfaces and trimming 
along buccal and lingual margins. 7, 8. For proximal surfaces, cutting through 
at contact point and trimming along gingival margins. 



then with suitable instruments first carve the occlusal surface 
to proper contour, carving flush to the marginal edges, leaving 
no overlap on the surface, the mass which is wedged into the 
proximal surface holding the filling in place during this oper- 
ation. 

The occlusal surface having been carved, with suitable in- 
struments proceed to carve the proximal surface, holding the 
wax in place by light pressure with an instrument on the 
occlusal surface. Do not attempt to carve thick slices off the 
wax, but simply shave it off with a movement parallel to the 
margin until -at last it is carved flush to the margin with no 
overlap remaining. The buccal and lingual sections should 
be carved before proceeding to carve the gingival section, 
finally passing a very thin instrument through the contact 
point and slicing off the portion which may have squeezed into the 
contour of the adjacent tooth. (Instruments suitable for this carving 
are shown in the accompanying illustration.) Fig. 273. Should the 
cavity extend rootwise considerably under the gum margin it may be 
necessary to adjust a matrix to secure an accurate margin at the 
gingival section, this should also be done in complex cavities includ- 
ing a large buccal or lingual section of the tooth as well as the 
proximal. In such cases it is well to note the character of the bite 
before adjusting the matrix, then carve the occlusal surface from 
memory, so to speak, afterwards remove the matrix, carve the buccal 



304 CONSTRUCTION OF GOLD INLAYS. 

and lingual proximal sections, then while thoroughly chilled have the 
patient close the teeth very carefully, if the occlusion be too high, note 
the point and carve it away. 

In cavities which include mesial, distal and occlusal surfaces it will 
be advisable to lit a band matrix which will encircle the tooth. This 
may be constructed of thin platinum or silver, and such a matrix 
when properly adjusted will not interfere in the least with the bite. 

The writer has encountered some cavities, however, to which a 
band matrix could not be adjusted and without which an accurate wax 
filling for the cavity could not be constructed. One of this character 
which he was called upon to fill recently was a lower left second molar, 
the cavity extending from the mesio-buccal angle around to the disto- 
lingual angle and the gingival margin of which lay about 2 mm. 
below the gum. The pericemental attachment was practically at the 
cavity margin and this would have precluded the adjustment of a 
band matrix even if the other difficulties to its adjustment could have 
been surmounted. 

The case was operated on as follows : 

An impression of the cavity was taken with base-plate gutta-percha, 
it being possible with this material in a semi-plastic condition to force it 
slightly over the cavity margin lying beneath the gum. From this 
impression a cement model was constructed, mounted in the die cup of 
one of the swaging machines and a 1/1000 platinum matrix was 
swaged and carefully trimmed to the gingival margin. 

This matrix was then adjusted in the cavity and trimmed just 
flush with the gingival margins, without overlap at any point, then 
a mass of inlay wax was softened and pressed into the matrix while 
in the cavity and the patient was allowed to bite on it. This was 
removed from the matrix and the matrix from the cavity, both matrix 
and wax were carefully dried, the wax was then placed in position 
in the matrix and the crevice that was found along the gingival margin 
between the wax and the matrix was rilled by carefully flowing melted 
wax into it by means of a small spatula; the wax filling now being 
adherent to the matrix it was replaced in the cavity, it was noted where 
additional contour was needed and wax was flowed on at that point, 
when the proper contour was at last obtained. Matrix and wax 
rilling were removed thoroughly chilled, then with a large spoon ex- 
cavator, a concavity was cut in the wax through the hole in the center 
of the matrix; this was to provide for additional mechanical retention 
of the inlay and may be resorted to in any inlay where the retentive 
shape of the cavity seems to be inadequate, and the securing of ad- 



CONSTRUCTION OF GOLD INLAYS. 305 

ditional retention would jeopardize the stability of the remainder of 
the crown of the tooth. 

The function of the platinum matrix in the case just referred to, 
was simply to give a definite edge to which the wax filling could be 
trimmed to secure an accurate adaptation to this obscure margin so that 
there would be neither protrusion or recession at the cavity margin, 
either of which would probably have caused chronic gingivitis. 
Subsequently, the gold was cast into this platinum matrix which became 
part of the permanent inlay. 

In case of pulpless teeth additional retention may be secured 
by inserting an iridio-platinum post (about 18-gauge) in the root 
canal. This should be inserted after the wax filling has been carved. 
Heat the post (see that it is dry and slightly roughened) and pass it 
through the wax filling into the root canal; it should be hot enough 
to melt the wax as it comes in contact with it so that it will pass through 
the filling without force enough to crowd it from the cavity. When 
chilled the wax will be adherent to the post and can be removed from 
the cavity by simply grasping the projecting end of the post and re- 
moving it and the filling together. 

If matrices or posts are used they should always be of platinum 
and iridio-platinum respectively, as gold matrices and posts oxidize 
slightly when the mold is heated up and the cast gold does not adhere 
perfectly to them. 

The wax filling having been completed and removed, it is chilled in 
ice water, then a little brass rod about 10 mm. long and 2 mm. in 
diameter, technically known as a sprue-former, is heated by dry heat, 
and pressed into the wax at either the occlusal or the proximal surface, 
preferably the latter, then the investment or mold material is mixed to 
about the consistency of thick cream. In mixing this simply sift the 
compound into the water, avoid stirring it so that there will be no 
bubbles. 

Dr. Taggart has devised two measuring cups, one for the water and 
the other for the compound which gives just the proper proportions. 
The compound sets slowly so that there is ample time for careful, 
deliberate application of it to the wax model. It should be applied 
with either a small sable brush or small pointed spatula; a little is 
laid on at a time and carefully worked into all the corners and 
angles, especially along the lines of the margins, then after all the 
surfaces have carefully been covered, more compound is added until 
the model is covered at all points with an investment about 2 mm. 
thick. 



306 CONSTRUCTION OF GOLD INLAYS. 

Then the case appears simply as a brass rod with a mass of in- 
vestment material on the end of it. This brass rod is now inserted into 
the hole in the center of the base plate of the molding flask which con- 
sists of a metal ring, and a base plate. The ring is about an inch in 
length, varying in diameter, according to the size of the casting to be 
made (for by this process a casting as extensive as that of a fourteen 
tooth bridge may be made), with a small hole in one side near the 
base to permit the surplus mold material to escape. 

The base plate is so constructed, that while it fits into the ring for a 
couple of millimeters there is also a flange section with a milled edge 
which extends beyond the side of the flask. In the center of base plate, 
is a dome and in the center of that there is a hole into which the sprue- 
former is inserted. Having set the sprue-former in position, put the 
ring in place on the base plate and fill it with the mold material or 
investment, slowly rotating the flask as you do so. 

Build up an excess above the top of the flask, then press a piece of 
glass plate down upon it which will force the excess through the 
little hole in the side of the flask. The glass plate is removed by 
sliding it across instead of lifting it. 

When the investment has set, the flask is heated slightly, then 
grasping the milled edge of the base plate it is gently turned. This 
breaks the adhesion of the mold material to it without disturbing the 
surface and the base plate and sprue-former are withdrawn from the 
mold. Do not invert the flask in doing this, for if this be done and 
some of the investment material should flake off it would drop into the 
sprue hole and result in a flaw in the casting. The base plate should 
be kept clean and polished at all times, rubbing off the surface after 
cleaning with a little vaseline. 

The base plate and sprue-former having been removed, there will 
be found a cup-shaped depression in the center, with a hole leading to 
the mold. The flask is placed over the Bunsen burner in an oven which 
has been devised by A. C. Clark & Co., and the case heated slowly, 
carrying the heat to a point where the wax is ignited. The case is 
kept at this heat until not only has the wax been burned out, but the 
residual gases therefrom have also been combusted. It is highly 
important that the mold be kept intact, to obtain a flawless casting. 
To insure this, heat the flask slowly and do not subject it to any greater 
heat than is necessary to consume the wax and its gases. 

Take precautions to avoid chipping the investment about the con- 
cavity and the sprue hole, for if these chips should fall into the mold 
and it frequently is impossible to remove them if they do, they cause a 



CONSTRUCTION OF GOLD INLAYS. 307 

faulty casting and if the fault be along any of the margins, your inlay is 
ruined beyond repair. 

The burning out of the wax and its gases being completed, the 
flask is grasped with tongs and placed in the flask holder of the casting 
machine. 

It may be well to briefly describe the casting machine. It consists 
of a device which holds a 100 gallon cylinder of nitrous oxide, has a 
pressure valve which may be set for the pressure desired, two dial 
pressure indicators, one of which registers the pressure in the cylinder 
and the other the pressure under which it is released, a blow pipe, a 
compressing lever, a mold flask holder, and a signal whistle which 
sounds until the escape valve of the gas cylinder has been closed after 
the casting has been made, a very valuable little device by the way 
which prevents the inadvertent loss of a cylinder of gas. 

The flask having been placed in the flask holder, a button of gold 
is placed in the cup-shaped depression of the mold and the flame of the 
nitrous oxide blow pipe is directed against it. The use of the nitrous 
oxide blow pipe concentrates a small intense flame directly upon the 
gold, melting it thoroughly without affecting the surrounding mold 
as the ordinary gas blow pipe flame would. 

The button of gold having been melted until it fairly boils, the 
compressing lever is brought down, thrusting aside and shutting off the 
blow pipe, forcing a metal cover, with asbestos rim packing to make it 
pressure tight, upon the flask ring and releasing upon the molten gold a 
gas pressure of about twelve pounds from the gas cylinder, forcing it 
into the mold in the center of the flask, the residual air being driven 
into the minute pores of the mold investment ahead of the gold. 

The various operations are done automatically by the downward 
sweep of the compressing lever. The whole operation is practically 
instantaneous, the molten gold has no opportunity to cool and solidify 
until it is forced into the mold ; the gas pressure is confined absolutely 
to the mass of gold and is sustained while it is cooling, and therein 
lies the main factor of success of this method. 

The flask is cooled, the investment broken out and a gold casting, 
the duplicate of the wax filling with a metal sprue attached is found. 

The metal sprue is cut off with a fine saw or pair of nippers, the 
gold inlay is immersed in hydrofluoric acid for a short time to remove 
the particles of investment material that will be found fused to it, 
then washed, boiled in sulphuric acid and washed again. Frequently 
the outer surface will need little or no polishing save at the point 
where the sprue was attached, so perfectly may castings be made 



;oS CONSTRUCTION OF GOLD INLAYS. 

by this process if the wax rilling be carefully finished and all the 
various steps carefully carried out. 

After trying in the inlay, if it should be found that the proximal 
contour is insufficient, this may be added to by simply flowing on a 
little 22-K solder at that point. It has been found by experience that 
it is not necessary to reheat the flask before placing it in the machine, 
should it have cooled off before the wax has been burned out; it must be 
perfectly dry, however, otherwise there will be a regurgitation of steam 
that will either blow the gold out of the depression when it is molten or 
prevent the complete casting, according to the amount of steam de- 
veloped. 

Incidentally it may be pointed out that this method allows one to 
obtain full value for gold scrap, as gold scrap containing even platinum, 
solder or clasp gold may be used. The scrap as scrap should be 
melted into a button before placing it into the flask. 

After many experiments the writer uses a gold alloy consisting of 
equal parts of 24-K gold and 22-K solder. Large inlays may be con- 
structed of this, without danger of flow of material under severe and 
continued stress of heavy mastication. 

The effectiveness of this casting device may be appreciated when 
you are informed that by it clasps may be perfectly cast of clasp 
gold. 

With this casting machine has been cast gold crowns upon platinum, 
bases; bridge section even up to those embracing the entire arch; clasps; 
retaining splints; partial plates; and even full plates may be cast. 

There is no question but what Dr. Taggart's invention of appliance 
and process marks a new epoch in both operative and prosthetic den- 
tistry; its value is such that the profession and the public are under 
obligation to him. 

Since his demonstration of appliance and process other appliances 
for casting have been devised and presented. One very ingenious ma- 
chine was originated by Dr. Jamieson, of Indianapolis. It casts by 
centrifugal force, the flask having a swivel handle is hung from a hook 
at the end of a horizontal rod about a foot long attached to an up- 
right rod which is revolved by the release of a spring at the rate of 
about 3000 revolutions a minute. 

Another device originated by Dr. Moll, of Chicago, casts by suction, 
a partial vacuum being created. Still another device, the originator 
of which the writer cannot ascertain, casts by means of steam pressure. 
A pad of moistened asbestos is jammed down upon the flask, the heat 
of the molten gold developing steam of sufficient pressure to force the 



CONSTRUCTION OF GOLD INLAYS. 309 

gold into the mold. The results by this method are uncertain, the 
writer experiencing fully 50 per cent of failures by it. 

All these methods, however, are based upon that of Dr. Taggart's, 
in that they employ a wax filling as a model and a flask for the mold 
identical with his, and it may be remarked that these were the most 
important factors of his invention, the solution of the casting device 
being the least difficult of the problems. 

The writer has tried all methods and devices for casting and after 
many experiences states unequivocally that Dr. Taggart's appliance 
has a wider scope and produces more uniform and more perfect re- 
sults than does any other. He holds no brief for the gentleman and is 
under no greater obligation to him than is any and every member of 
the profession. The statement is made simply because it is a fact. 

This process supplants all others because better results can be 
obtained with less labor for the operator and less loss of time for both 
operator and patient. 

Just a word of serious warning in closing this chapter to those 
about to employ this method. Do not imagine that it discounts care 
and skill. One may think it is no trick at all to construct a wax filling 
for a cavity, but let me assure you, and experience will emphasize it, 
that it requires all the skill and patience you possess most of the time to 
properly construct this wax filling and you will probably be discouraged 
with the process and your endeavors, until you have mastered the 
manipulative technique; for faulty wax fillings will invariably result in 
faulty inlays. 

Skill, care and cleanliness must be observed in all steps of this 
process. Once the manipulative technique peculiar to this process has 
been mastered, one will discover that instead of discounting, it puts a 
premium on individual skill and carefullness. For by this process 
more uniform and better results with less labor may be obtained than 
have heretofore been possible with any process at our command. 



CHAPTER XVIII. 

THE TREATMENT OF EXPOSED OR NEARLY 
EXPOSED PULPS. 

BY J. P. BUCKLEY, PH.G., D. D. S. 
GENERAL CONSIDERATIONS. 

In the practice of dentistry there are problems continually arising 
wherein it is difficult for the conscientious operator to decide upon a 
method of procedure which will conserve the best interests of the patient. 
There is no condition confronting us with greater difficulty than in 
those cases where the decay has extended to such a depth that its thor- 
ough removal will expose or nearly expose the pulp. The problem to 
be solved here in all such cases is to decide whether it will be best to 
try to save the pulp or to anesthetize or devitalize this organ, remove it 
and subsequently fill the canals. 

There are several important factors to be considered, and upon 
which will largely depend the success or failure following an attempt 
to save the pulp after it has actually been exposed. In an accidental 
exposure in the preparation of a cavity, the chances for saving the pulp, 
provided the injury has not been too great, are far more favorable than 
if the pulp had been exposed by the necessary removal of carious dentin. 
Our success will also depend in no small degree upon the condition of 
the pulp as well as upon the general condition of the mouth of the pa- 
tient in which the exposure occurs. If there is congestion or any evi- 
dence of degeneration of the structural components of the pulpal organ 
itself, it would be futile to attempt to cap it, as would be also any attempt 
to permanently save a pulp in the mouth of a patient who was suffering 
from some systemic derangement interfering with the general circula- 
tion, thus lessening vital resistance; for in such cases the pulp would 
fail to receive from the blood supply the necessary elements for the 
restoration of its functional activity. The general condition of the 
mouth itself and the care it receives daily from the patient, is an essen- 
tial factor to be taken into consideration before proceeding to cap a 
pulp. Dr. S. A. Hopkins, of Boston, in a carefully conducted series 
of experiments to ascertain the difference in virulency of certain path- 
ogenic bacteria in different mouths, and in the same mouth under 

3 TI 



3 1 2 TREATMENT OF EXPOSED OR NEARLY EXPOSED PULP. 

different conditions, proved that not only did the germs proliferate 
more rapidly in neglected and uncared-for mouths, but their pathogenic 
properties are greatly increased. 

There is one class of cases of pulp exposure which frequently pre- 
sents in a busy practice and in which it is our plain duty to make the 
attempt to restore the organ to its normal function, even though the 
conditions for doing so are not altogether favorable. I mean here 
those cases in the mouths of young patients where the pulp is exposed 
from decay and the roots of the tooth have not been fully developed. 
Every effort should be made to cap such a pulp and thereby save it, 
if for only a year or two, for clinical experience has demonstrated that 
to remove the pulp and properly close the large openings in the end 
of the roots is, at best, a difficult procedure; that a tooth in this condi- 
tion, thus treated, is usually a source of annoyance and its usefulness 
generally of short duration. 

In another class of cases the author also believes that we are justi- 
fied in capping the pulp. For instance, in those cases of exposure 
where for certain reasons it is desirable to save the tooth, and on which 
it would be difficult to adjust the rubber dam, aseptically remove the 
pulp and thoroughly fill the canals. I wish to state here, however, that 
I do not mean to infer that a pulp should be capped in an anterior tooth, 
because of the liability of the tooth structure discoloring after the pulp 
has been removed. This phase of the subject will be referred to in 
detail in a subsequent chapter on pulp removal under the preservation 
of the color of the tooth. 

From the foregoing, then, it should readily be understood that no 
set of rules can be given, the application of which will surely lead to 
success. Every case must be studied and treated according to the 
operator's best judgment after having taken into consideration all 
these various factors. 

CAPPING THE PULP. 

There are several methods of capping the pulp, each differing in 
minor details, such as the use of various cements, gutta-percha, con- 
cave metallic discs, etc., etc. In the remainder of this chapter attention 
will be directed to the general precautions to be taken in following the 
different methods of capping; after which one method will be described 
in detail which has proved successful in the author's practice. By 
this I do not mean to convey the idea that all pulps which I have at- 
tempted to save have been rehabilitated to their functional activity — 
many have not; however, a sufficient number of those thus treated have 






CAPPING THE PULP. 313 

remained quiet, and proved years later to be vital, to justify making 
the attempt where the case demands. 

Precautions. — The precautions to be observed in following any 
method are: 

(1) By the use of an anodyne, the hyperemic pulp, if in this con- 
dition, must be restored to normal before the final capping. 

(2) The dentin overlying the pulp must be thoroughly sterilized. 
It should be noted here that the usual perfunctory method of sterilizing 
the dentin by simply applying a germicidal solution to the cavity for 
a few moments does not sterilize to the degree necessary for successful 
results. The lack of thorough sterilization has, without doubt, been 
the chief cause of failure. The accuracy of this statement will be seen 
when we remember that our greatest success has followed the capping 
of pulps which have been accidentally exposed with a bur or instru- 
ment in preparing a cavity, although, in most cases, greater mechanical 
injury had been caused than when the exposure was due to caries or 
the removal of carious dentin. 

(3) Pressure in applying the material for capping, or the cement 
which covers the capping, must be avoided. 

Technique. — After breaking down all overhanging edges of enamel 
and removing as much of the debris and softened dentin as can be done 
without pain or injury to the pulp, the cavity should be flooded with a 
mild, non-irritating, antiseptic solution, previously heated to the tem- 
perature of the body. For this purpose the author suggests the use of 
peppermint water to which 95 per cent phenol has been added in the 
following proportion: 

T} Phenolis, f. o j 

Aquae menthae piperitae, f. § vj — M. 

Sig. — Use wherever a mild, non-irritating antiseptic 
solution is indicated. 

This solution can be further diluted, if necessary, and used with a 
water syringe, before applying the rubber dam, thus adding comfort and 
cleanliness to the operation. The excess can now be absorbed from 
the cavity with cotton and the dam adjusted. By using some obtund- 
ing remedy and a sharp spoon excavator, or oftentimes a large round 
bur in the engine, the carious dentin can be removed. If, however, 
the thorough removal of all the softened dentin would make a large 
exposure, it is best to leave the layer overlying the pulp and depend 
upon the sterilizing agent, rather than to jeopardize the life of this 
organ by the .injury thus produced. The delicate pulp tissue will not 
tolerate much abuse and remain quiet, therefore if it is injured to any 



3 M TREATMENT OF EXPOSED OR NEARLY EXPOSED PULP. 

great extent it had better be removed at once. The dentin can now be 
sterilized by sealing in the cavity, for a week or two, the following 
remedy which is not only germicidal in action, but possesses marked 
anodyne properties as well: 

3— Menthol, 5 j 

Thymol, 5 ij 

Phenolis, q. s. ad., f. 5 iij — M. 

Heat the phenol and then carefully add the 
menthol and thymol. 
Sig. — Use as directed. 

For convenience this remedy will be called modified phenol. 

It is best to seal with a veneer of quick-setting cement, previously 
filling most of the cavity with cotton, thereby avoiding pressure and 
facilitating the subsequent removal of the dressing. By this means 
the dentin can be thoroughly sterilized, and the pulp, if at all hyperemic, 
as it is likely to be, will return to its normal condition. 

Thymol has a peculiar but favorable action on animal tissue, 
and for this reason it is incorporated in the prescription. At the 
next sitting, the case giving a favorable history for the interval, 
the dam should always be applied, the teeth included sterilized 
and the previous dressing carefully removed, when the exposure 
and dentin immediately over the pulp can be gently covered with a 
thin paste made by mixing pure precipitated calcium phosphate with 
modified phenol, oil of cloves, or eugenol. The paste should be placed 
on one side of the cavity and gently coaxed over the exposure in such 
a manner as to exclude the air. I desire to emphasize the importance 
of covering the entire dentin immediately over the pulp, as well as the 
exposure, with this antiseptic and non-irritating paste. By this means 
we prevent the phosphoric acid of the cement, used to cover the paste 
and to temporarily fill the cavity, from irritating the pulp. It is best, 
as intimated here, to fill the entire cavity with cement and wait for a 
few months or perhaps a year before inserting the permanent filling 
or inlay. Advantage should be taken of every possible means of pre- 
venting subsequent irritation to the pulp. For this reason largely the 
author uses precipitated calcium phosphate instead of calcined zinc 
oxid, which latter substance is recommended by many writers. The 
powder (largely zinc oxid) which comes with a package of cement is 
supposed to be chemically pure. Those who are familiar with the 
science of chemistry, however, know that arsenic is found associated 
in nature with many of the metals, among which is zinc; and, while it 
can be done, it is difficult to obtain these metals or their oxids free from 



CAPPING THE PULP. 315 

arsenic. It is well, especially in those cases where the pulp is not 
quite exposed, to add a small amount of either aristol or europhen to the 
paste. These are iodin compounds and are used as substitutes for 
iodoform. Both are tasteless, practically without odor, and insoluble 
in water, but soluble in the oil used as the vehicle for the paste, there- 
fore only a small amount should be added. 

In closing this chapter, I desire to emphasize the importance of 
studying carefully the conditions as found in each case; and to say that 
the opportunity here for exercising good judgment is very great, and 
that there is a satisfaction in realizing, whether we succeed or fail in 
our effort to save the pulp, that we did our duty as we saw it. 



CHAPTER XIX. 

THE ANESTHETIZATION AND DEVITALIZATION 

OF PULPS, THEIR REMOVAL, AND THE 

SUBSEQUENT TREATMENT. 

BY J. P. BUCKLEY, PH. G., D. D. S. 
GENERAL CONSIDERATIONS. 

Embryologists claim that when the roots of a tooth are fully devel- 
oped, the pulp has no further function to perform. If this theory can 
be accepted as correct, and I think that it is quite well established, it 
would appear from the large percentage of failures following the most 
careful methods of pulp capping, that the safest, and, therefore, the 
best practice would be to destroy the vitality and remove the pulp in all 
cases where this delicate and susceptible tissue had been previously 
irritated for any great length of time, unless, as explained in the fore- 
going chapter, there was some special reason for attempting to restore 
the organ to its functional activity. From sad past experience the 
author has been led to adopt this general practice. By this I do not 
wish to convey the idea that it is advisable or necessary to miscellane- 
ously or ruthlessly destroy pulps, for such is not the case. It is the 
plain duty of every dental practitioner to save the pulps of teeth, if it 
can be done with any reasonable degree of success. There are many 
conditions, however, which necessitate the removal of the pulp, such as: 

(i) Dental caries, or the invasion of pathogenic bacteria and the 
absorption of ptomains. This is the most prolific source of pulp irrita- 
tion. 

(2) Mechanical irritation, due to such causes as abrasion, thermal 
changes, close proximity of metallic fillings, injudicious regulating, 
excessive grinding, etc. 

(3) Calcific deposits, or pulp nodules within the pulp itself. These 
calcific bodies result from slight but continued irritation of the pulpal 
organ. 

(4) Crowning teeth and filling large cavities. It is usually diffi- 
cult to grind a vital tooth sufficiently to adjust the band for a crown 
properly, without irritating the pulp and thus endangering its life. 
Sometimes in rilling teeth it is advisable to remove the pulp in order to 
properly anchor a large filling or inlay. 

3 J 7 



318 THE ANESTHETIZATION AND DEVITALIZATION OF PULPS. 

(5) Pyorrhea alveolar is. Frequently in treating this disease the 
best results can be accomplished by removing the pulp and thereby 
throwing the entire circulation to the sluggish pericemental mem- 
brane. 

Factors to be Observed in Removal of Pulp. — Having considered 
all of the conditions and deciding that the removal of the pulp is in- 
dicated, the method by which this can be accomplished with the least 
inconvenience to the patient and to the operator is the most important 
consideration. Whatever method is employed in the removal of pulps 
from teeth and the subsequent treatment, there are at least three fac- 
tors to be observed, viz.: 

(1) Establish and maintain asepsis in performing the operation. 

(2) Preserve the color of the tooth. 

(3) Thoroughly fill the root. 

METHODS. 

I. Anesthetization. — In the author's opinion a very satisfactory 
method of removing pulps from teeth, to both patient and operator, 
all things considered and conditions being favorable, is to anesthetize 
the tissue by the use of various strength solutions of local anesthetic 
agents. The solutions are forced or carried through the dentin and 
into the pulp by means of pressure or the electric current. 

(1) Pressure Anesthesia. — By pressure anesthesia is meant the 
process of anesthetizing the pulp by forcing solutions of local anesthetics, 
usually cocain hydrochlorid, into the tissue by means of pressure. The 
pressure is applied either by using unvulcanized rubber or gutta-percha, 
and a blunt instrument, or by specially devised instruments for this 
purpose. There are many such instruments on the market ; and while 
they are often an aid in accomplishing the ultimate result, they are not 
an absolute necessity. 

The rubber dam should be employed in every case where it is pos- 
sible to adjust it, and the teeth included sterilized. In cases where the 
dam cannot be adjusted, it would doubtless be best to remove the pulp 
by the devitalization method, to which reference will be made later in 
this chapter, for in using the method under consideration care must be 
taken to prevent pericementitis following the operation; and one of the 
precautions to be observed in preventing this result is to thoroughly 
sterilize the cavity before applying the pressure. It should be remem- 
bered that the majority of canals which contain live pulps are sterile, 
generally speaking, and if they become septic at any time before the 
root is filled, it is the fault of the operator. Thus the importance of 






METHODS. 319 

always adjusting the rubber dam, using sterile instruments, and having 
in a convenient and conspicuous place an antiseptic doily on which to 
wipe the blood and dry the instruments used. 

Attention is again directed to the fact that the usual custom of apply- 
ing coagulating agents, such as phenol, cresol, etc., to the cavity for a 
few seconds, does not sterilize the dentin to the degree desired. The 
best results are accomplished by employing germicidal agents which are 
soluble in water. In cavities where the decay is not too deep, the den- 
tin can be sterilized by the use of a 10 per cent solution of formaldehyd 
to which 5 per cent of sodium borate (borax) or sodium carbonate 
has been added. Where the decay is near the pulp this solution is 
liable to cause pain, in which case the same result can be accomplished 
by the use of a 1:500 solution of mercury bichlorid. In using the 
latter solution the pliers on which the remedy is applied should be 
wiped immediately on an antiseptic doily to prevent the mercury 
from acting upon the instrument. One of the best solutions with 
which to chemically sterilize the dentin, especially in those cases where 
the cavity has previously been filled and the tubuli are closed and per- 
haps there is secondary dentin, is a 25 per cent solution of sulphuric 
acid. Dr. Geo. W. Cook, of Chicago, recommends using pure sul- 
phuric acid for this purpose. The solution can be applied to the floor 
of the cavity, being careful not to get the agent on the crown of the 
tooth. After a few minutes the excess can be neutralized w r ith a solu- 
tion of sodium bicarbonate. After the dentin is sterilized the cavity 
should be desiccated with warm alcohol and gentle heat, when we are 
ready to use the anesthetizing solution. Before taking up the technique 
of this method, however, I desire to emphasize the importance and 
necessity of cavity sterilization. In our discussion later of the devitali- 
zation method, it will be pointed out that the carious and infected 
dentin can be completely and painlessly removed after the devitalizing 
agent has been applied, thus mechanically sterilizing the cavity; but 
in the anesthetization method the infected dentin is sensitive and can- 
not be removed without unnecessarily producing pain. The dentin 
in this case must, then, be sterilized by chemical means, for to force 
the anesthetizing solution through the dentin without previously ster- 
ilizing it, means the forcing of microorganisms, and perhaps poisonous 
ptomains, into the pulp tissue and many times into the tissue surround- 
ing the apical end of the root, for it is difficult to force the solution to, 
and only to, the apex; thus too much pressure and the lack of thorough 
sterilization constitute a prolific source of pericementitis following the 
removal of pulps by this method. 



320 THE ANESTHETIZATION AND DEVITALIZATION OF PULPS. 

With the cavity thoroughly sterilized we are now ready to use the 
anesthetizing solution, which should be made at the time. For this 
purpose the crystals of cocain hydrochlorid, previously powdered, 
should be used as the base, and freshly distilled or boiled water as the 
vehicle. In my own practice I use the flaked cocain hydrochlorid as 
the base and my regular local anesthetic solution as the vehicle for 
making the stronger solution. A prescription for the regular local 
anesthetic solution here follows: 

1$ — Cocainae hydrochloridi, gr. vj 

Phenolis, m. ij 

Aquae menthae piperitae, f. § j — M. 

Sig. — Use as a local anesthetic for hypodermic injections. 

The flaked cocain hydrochlorid not only insures a pure specimen 
of the drug, but facilitates making the solution, as the flakes are so 
readily soluble. There is no advantage in using the above solution 
over distilled or boiled water or freshly prepared peppermint water, 
except that the solution is always at hand in a convenient container 
and is sterile. 

The thumb and forefinger with which cotton is to be wrapped 
around the broach should be sterilized by dipping a large pledget of 
cotton in the 10 per cent formaldehyd or i : 500 mercury bichlorid 
solution and rolling this between the thumb and finger. A small 
amount of the alkaloidal salt is now placed on a clean glass slab and a 
pledget of cotton, dipped in the vehicle selected, a few drops of which 
have previously been placed on one end of the glass slab or in a clean 
glass watch crystal or other container, is gently placed -in contact with 
the flakes, when the latter readily dissolves, making a strong solution. 
It is never necessary to make a saturated solution, for oftentimes better 
results will be obtained, especially if the solution is to be forced through 
the dentin, if the strength of the solution approximates only 4 or 5 per 
cent. 

The cotton thus saturated is placed in the cavity as nearly over the 
pulp as possible. A piece of unvulcanized rubber which will approx- 
imately fill the cavity is selected and passed through the flame. There 
are two objects in doing this: It sterilizes the rubber, and also makes 
it more pliable in which form it conforms readily to the cavity of the 
tooth. The rubber is now placed in the cavity, and by means of 
gentle but firm pressure with a suitable blunt instrument the solution 
is forped through the dentin and into the pulp. If there is any evidence 
of pain as the pressure is applied, it should be stopped for a moment, 
but never released. The slight pain is only momentary and is an in- 



METHODS. 321 

dication that the solution is being confined under the pressure, which 
is essential for the success of this method. It may be necessary in 
those cases where there is considerable dentin between the cavity 
and the pulp to make two or three applications before the pulp is 
reached without pain, after which one application should complete 
the thorough anesthetization of the organ. After the first application 
a small depression can be drilled into the dentin toward the pulp, in 
which the solution can subsequently be placed, thereby aiding materi- 
ally in confining the solution under the pressure. When an exposure 
exists it requires but little pressure to anesthetize the pulp. In these 
cases the cocain hydrochlorid can be placed in the cavity near or over 
the exposure and the pulp gently pricked with a sharp explorer, causing 
it to bleed; this if done carefully will produce very little pain. The 
blood will dissolve the cocain hydrochlorid, when pressure can be 
applied and the pulp anesthetized. In doing this, however, there is 
greater danger of forcing the blood into the tubuli of the dentin of the 
crown of the tooth, thereby making it more difficult to remove the blood. 
Care should also be taken not to force the solution any further than is 
necessary for the painless removal of the pulp, for it should be noted 
here again that cocain is a general protoplasmic poison, and if even 
weak and sterile solutions are forced past the apices of the roots peri- 
cementitis is almost sure to follow. 

When the pulp is anesthetized the pulp chamber should be opened 
into in such a manner as to expose the canals. This is best accom- 
plished with a large round or inlay bur by means of which the entire 
roof of the chamber can be obliterated. In opening into the pulp 
chamber of molar teeth care should be taken not to disturb the floor 
of the chamber, for by so doing we are liable to add to the difficulty of 
entering the canals with a broach. While we are never justified in 
drilling unnecessarily for the purpose of freely exposing the canals, 
it is, if necessary, far better to weaken the crown of the tooth somewhat 
by this means rather than leave a portion of the pulp in an inaccessible 
canal which may decompose and subsequently cause an abscess. 

The selection of a proper broach is an important matter. Every 
broach should be tested before entering the canal. This can be done 
by bending it in various directions. If the broach is weak in any 
particular place it can be detected by this means; thus we avoid break- 
ing the broach in the canal, the removal of which is often a difficult 
procedure. Many good operators claim to be able to remove all pulps 
by using a smooth, three-cornered broach on which a few threads of 
cotton are wound. Others use twist or spiral broaches. In all large 



canals the author has had the most satisfaction from the use of a barbed 
broach. The broach should be gently worked along the side of the 
canal as far as it will go without using too much force, twisted once or 
twice to entangle the pulp, and then withdrawn. By this means the 
pulp can be removed from large canals in its entirety. 

In the removal of live pulps by the anesthetization method, there 
necessarily would be more hemorrhage than in those cases where the 
pulp was devitalized before attempting to remove it. However, the 
control of hemorrhage is not as difficult a procedure as many writers 
have led us to believe. In most cases the hemorrhage, if undisturbed. 
will be checked by nature's method in a few minutes; after which the 
blood in the cavity and canal should be thoroughly removed. I desire 
here to emphasize the importance of removing the blood. One of the 
factors to be observed in extirpating pulps from teeth and the subse- 
quent treatment, is to preserve the color of the tooth. The cause of 
many teeth darkening after the pulp has been removed, can be traced 
directly to the failure to remove the blood from the dentin of the crown 
of the tooth. The far too prevalent practice of wiping out the bloody 
canal with a solution of hydrogen dioxid, blindly thinking the blood 
can be removed by this means, cannot be too strongly condemned. 
The hydrogen dioxid simply decomposes the blood within the tooth 
structure, oxidizing the iron of the hemoglobin; and the gases evolved 
in the decomposition force this pigment into the tubuli, which, if left 
(and it is difficult to remove it), will cause the tooth to darken in almost 
every instance. In a subsequent chapter the author expects to show 
that ferric oxid is largely responsible for the discoloration of teeth from 
pulp decomposition. Therefore w r e should avoid forming w T ithin the 
tooth structure the pigment which we know will discolor teeth. The 
color of a tooth does not depend upon the life and vitality of the pulp, 
but upon the array of colors in the dentin which are reflected through the 
nearly colorless and transparent enamel. If, then, these colors are not 
changed by our failure to remove the blood or by the use of staining 
remedial agents in the subsequent treatment following pulp removal, 
the tooth will not discolor. 

To remove the blood from the canal, alcohol can be used, or even 
better than this agent is nature's greatest solvent, water. The water 
should, of course, be sterile, and the same specimen can be employed 
here as was used in making the anesthetizing solution, i. e., freshly 
distilled or boiled water, or peppermint w r ater to w T hich two 
minims of phenol has been added to the fluid ounce. If convenient, 
a little sodium chlorid (common salt) can be added to the water. By 



METHODS. 323 

this means the blood can be completely removed, not decomposed in 
the canal and forced into the structure of the tooth. 

There are many canals so small and tortuous that even a fine 
broach will not enter, to any depth at least. In these cases, after the 
hemorrhage from the larger canals has been checked and the blood re- 
moved, the pulp tissue in the small canals can be disorganized by the 
use of strong solutions of mineral acids or alkalies. The author pre- 
fers making a paste of sodium dioxid and absolute alcohol, placing the 
paste in the pulp chamber over the small canals, and working it down 
as far as possible with a smooth broach. The alcohol gradually evap- 
orates, when the sodium dioxid can be decomposed into oxygen and 
caustic soda by placing a pledget of cotton in the cavity moistened with 
distilled water. After the reaction has taken place, the alkali can be 
neutralized with a weak solution of sulphuric acid (2 per cent) . This 
process can be repeated until the desired end is attained. There are 
other means by which the same result can be accomplished, such as 
the use of pure phenolsulphonic acid, a 50 per cent solution of chem- 
ically pure sulphuric acid, strong solutions of sodium or potassium 
hydroxid, or a mixture of metallic sodium and potassium (Schreier's 
paste). These same agents, especially the phenolsulphonic acid, can 
be used to advantage for the purpose of disposing of a remnant of a 
pulp in larger canals. It is not safe to anesthetize this remnant by 
means of pressure. The only cases on record to my knowledge, where 
toxic symptoms have resulted from the removal of a pulp by pressure 
anesthesia, followed an attempt to anesthetize a remnant of a pulp or 
in making the second application of the anesthetizing solution. 

After the pulp has been removed and the canals dehydrated with 
alcohol and heat, an anodyne treatment is indicated. For this purpose 
such drugs as phenol, oil of cloves, or eugenol can be employed. The 
author suggests here the modified phenol solution to which attention 
was called in the chapter on The Treatment of Exposed or Nearly 
Exposed Pulps. In using any of these remedies, especially the last 
named, it is best to insert dry cotton in the canal and then place a 
pledget dipped in the remedy in the pulp chamber and seal with tem- 
porary stopping or cement. The dry cotton in the canal will absorb the 
moisture from the apical end of the root and the anodyne remedy from 
the pulp chamber. There is an advantage in using the dry cotton, 
for it is almost impossible to completely dehydrate the canal at this 
sitting. If asepsis has been maintained in removing the pulp all that 
is necessary is to keep the canal in this condition until the root can be 
filled. The canals should not be filled at the sitting at which the pulp 



324 THE ANESTHETIZATION AND DEVITALIZATION OF PULPS. 

has been removed by pressure anesthesia unless there be some excep- 
tional reason for doing so. There are many good reasons why the 
canal should not be rilled at this sitting: 

(1) While it is our object to force the solution just sufficiently to anes- 
thetize the pulp, our main object is to remove the pulp absolutely 
without pain, and it is very difficult to force the solution to the end 
of the root without forcing it through the apex and anesthetizing 
the tissue in the apical area to some extent. With the tissue anes- 
thetized we would have no guide as to when the root was thoroughly 
filled. 

(2) The tearing away of the pulp from its connection at the apex 
causes more or less irritation, and a few days should elapse to give 
nature a chance to readjust the condition. The root filling would 
only serve at this time to further irritate the tissues. 

(3) Sometimes with the utmost care in removing the pulp, secondary 
hemorrhage ensues with the formation of a clot in the apical area, 
causing soreness, in which case greater comfort can be given the 
patient by the proper treatment through the root canal than simply 
by counterirritation or external treatment only. 

At the second sitting, the case giving a favorable history, the canals 
should be filled. 

There are cases occasionally where nature does not stop the hemor- 
rhage as readily as we desire. In these exceptional cases the hemorrhage 
must be stopped by artificial means, even at the possible expense of 
producing pericementitis. Cauterizing agents are useful here. For 
this purpose 95 per cent phenol, a 50 per cent solution of phenolsul- 
phonic acid, or a 15 per cent solution of trichloracetic acid, can be 
w r orked down into the canal against the injured and bleeding tissue, 
after which the anodyne treatment is employed as usual. Where the 
above treatment does not produce the desired result, cotton saturated 
with a fresh 1 : 1000 solution of adrenalin chlorid can be placed in the 
canal and with unvulcanized rubber forced into the tissue beyond the 
end of the root. This should only be used in extreme cases because of 
the soreness it is liable to produce. 

In this connection I desire to discuss the use of solutions of adren- 
alin chlorid as the vehicle for making the anesthetizing solution, or 
the use of adrenalin chlorid and cocain hydrochlorid tablets for anes- 
thetizing the pulp. The adrenalin chlorid has been suggested as a 
means of preventing hemorrhage. Now, it ought to be evident to any 
one who has studied this subject that to prevent hemorrhage by the use 
of any hemostatic agent, it is necessary to force the agent into the 



METHODS. 325 

tissue from which the hemorrahge comes. Therefore, to get the 
effect of the adrenalin chlorid in removing pulps by pressure anesthe- 
sia, it is absolutely essential that the anesthetizing solution which also 
contains the hemostatic agent, be forced through the apex and into the 
apical area — the very thing we have been taught, from sad experience, 
not to do. When we remember that the majority of pulps we are called 
upon to remove are those in which there is, or has been, more or less 
pulpitis, and when we remember also that pathology teaches that this 
condition is frequently associated with pericementitis, it is questionable 
whether or not we ought to prevent hemorrhage in removing pulps 
from teeth. For to permit the escape of blood from the hyperemic 
tissue at the end of the root, is one of the best means of aiding nature to 
readjust the abnormal to the normal condition. In case the primary 
hemorrhage has been prevented by the use of hemostatic agents, such 
as adrenalin chlorid, secondary hemorrhage is almost certain to follow 
with the formation of a clot, the absorption of which in the apical area 
is an extremely slow and tedious process. 

In removing pulps by pressure anesthesia without employing in- 
struments devised for this purpose, the best results are obtained in 
cases where there are four walls to the cavity,, for in this condition the 
solution is easily confined under the pressure. In proximo-occlusal 
cavities, the missing wall can be built temporarily with gutta-percha 
or cement. This is seldom necessary, however, if, in packing the 
rubber in the cavity, care be taken to cover the gingival wall first and 
thus seal at this point, then working the rubber over the occlusal and 
gradually creating the pressure. Whatever means is adopted for the 
purpose of confining the solution, we must avoid having the solution 
escape at the gingival margin of the cavity and thereby be forced into 
the gum tissue and pericemental membrane. The cause of many sore 
teeth following this method of removing pulps, can be traced to care- 
lessness or ignorance in this regard. As stated elsewhere in this 
chapter, there are many ingeniously devised instruments on the market, 
the use of which is often a material aid in confining the solution under 
pressure and forcing it through the dentin. The same precautions 
should be observed in using any of these instruments as have been 
emphasized in the application of pressure by other means. 

(2) Cataphoresis. — Cataphoresis is a term applied to the process 
of carrying medicinal agents in solution into the various tissues and 
organs of the body by means of the electric current. There is a variety 
of cataphoric outfits on the market. To anesthetize a pulp by this 
means the tooth should be insulated by the rubber dam, care being 



320 THE ANESTHETIZATION AND DEVITALIZATION OF PULPS. 

taken that no moisture escapes from the gum. A small pledget of 
cotton saturated with the anesthetizing solution is now placed in the 
cavity, the positive electrode applied to the solution, and the negative 
electrode, moistened with water, applied to some part of the patient's 
body, usually the hand, thus completing the circuit. A steady and con- 
tinuous current is desired and the perfected instruments are so devised 
that the amount of current can be measured. The time required to 
anesthetize the pulp by this means depends largely upon the density 
of the dentin and the perfection of the instruments used. With the 
pulp anesthetized, the same method of removing and the subsequent 
treatment is followed as in pressure anesthesia, Cataphoresis, while 
successful in the hands of those who mastered the technique, never be- 
came popular, largely because of the time required to accomplish the 
result and because of the complicated and expensive apparatus nec- 
essary. 

If the method of anesthetizing the pulp be followed and the pre- 
cautions observed as detailed in this chapter, it will be found that 
there are few pulps which will not yield to the influence of cocain hy- 
drochlorid. It takes time, however, to adjust the rubber dam, ster- 
ilize the cavity, remove the pulp and blood from the canal and seal in 
the anodyne remedy. Many times the operator is not able at this sit- 
ting to give the necessary time to complete this operation. There are 
cases also where the condition or the location of the tooth in the mouth is 
such as to make the removal of the pulp more favorable by another 
method which will now be considered. 

II. Devitalization. — In the chapter on The Treatment of Sensi- 
tive Dentin under the subject of escharotics or caustics, reference was 
made to the fact that there were many drugs belonging to this class of 
agents that could not be employed in the treatment of sensitive dentin, 
for the reason that they were penetrating and had the same deleterious 
effect upon the cells of the pulp tissue as upon the dentinal fibrillar. 
Some of the agents which cannot be used for allaying the sensitiveness 
of dentin are exceedingly valuable and are employed for the purpose 
of destroying the vitality of the pulp, thus aiding in its painless removal. 
The most prominent of these agents is arsenic trioxid, (As 2 3 ), formerly 
called arsenious acid. The author is again gratified to know that 
the latest edition of the United States Pharmacopeia recognizes this 
agent by its correct chemical name, for he was never able to understand 
why a true oxid should be called an acid by our legal authority. Ar- 
senic trioxid was introduced to the dental profession in about 1836 by a 
Dr. Spooner, of Montreal. The agent was first advocated to be used in 



METHODS. 327 

the treatment of sensitive dentin; for Dr. Spooner discovered that by 
sealing the drug in a cavity for a few days the most sensitive dentin 
yielded to its influence. The fact, however, that nearly all teeth thus 
treated subsequently gave trouble because of the death of the pulp and 
the usual sequelae, led the profession to abandon this agent for the 
purpose for which it was introduced; but it has ever since been used as a 
means of destroying the vitality of the pulp. In fact, for years it was 
the only agent employed with any satisfaction. 

There has been much difficulty experienced in the use of arsenic 
trioxid, largely because of the uncertainty of the preparations employed. 
Many arsenical preparations are on the market. The white powder 
can be used by moistening a small pledget of cotton with some liquid, 
such as phenol, cresol, creosote, or oil of cloves, then by touching the 
cotton to the powdered arsenic trioxid, a sufficient amount will adhere 
which should be transferred to the cavity and sealed, preferably with 
cement. It is well for each operator to select an arsenical preparation 
with which he can obtain good results, and then this should be used 
to the exclusion of all others. By this means only can we become 
thoroughly familiar with the action of the preparation employed. The 
author prefers a paste, a formula for which is here given: 

R — Arseni trioxidi, 3 j 

Cocainae, gr. xx 

Menthol, gr. v 

Lanolini, q. s. ft. stiff paste — M. 

Sig. — Apply a small amount to the dentin immediately 

over the pulp. 
Note : A sufficient amount of lampblack should be added 
to color the paste. 

I wish to state here something about the pharmacy of this pre- 
scription; for if the preparation does not work satisfactorily, it has not 
been properly compounded. Arsenic trioxid is the base, cocain is a 
local anesthetic, and when applied to the pulp produces a condition of 
analgesia by which the irritating action of the arsenic trioxid is without 
effect, and thus prevents the tooth from aching while the pulp is being 
devitalized. With the fatty or oily vehicle, lanolin, it is best to use the 
alkaloid, cocain, rather than the alkaloidal salt, cocain hydrochlorid; 
and the less the amount of lanolin used the better will be the action of 
the base. For this reason largely menthol is added. This agent is 
a highly deliquescent substance, and there is a sufficient amount of 
water in the lanolin to liquefy the crystals of menthol, therefore it 
requires but a small amount of lanolin with the menthol to make a 
paste out of the arsenic trioxid and cocain. 



;_S nu: anesthetization and devitalization of pulps. 

In those cases where the tooth has ached before the patient presents 
for treatment, it is always the best practice to allay the pain for at least 
twenty-four hours before attempting to devitalize the pulp. In any 
ease, whether the tooth has ached or not, before applying the arsenical 
preparation or before adjusting the rubber dam, it is best to break 
down all overhanging edges of enamel and carefully remove or w-ash 
out with a non-irritating antiseptic solution any food- stuffs or debris 
which may be in the cavity. Food- stuffs contain albumin, and if such 
is in the cavity of the tooth when the arsenical preparation is applied, 
the arsenic trioxid will act upon the albumin, forming the arsenic 
albuminate, and thereby a certain amount of the agent is neutralized 
or becomes inert. As much of the carious dentin should also be re- 
moved as can be done without producing pain, for the application 
should be made to a sensitive spot in the cavity. It is never necessary 
to have an exposure of the pulp; and in case an exposure exists, it is 
best to apply the preparation to the dentin immediately over the pulp, 
rather than directly to the organ itself. The preparation should be 
covered with cotton or small metallic or paper disc to prevent pres- 
sure and also to prevent the phosphoric acid of the cement from com- 
ing in contact with the ingredients of the paste. 

There are at least four factors w r hich govern the length of time an 
arsenical application should remain sealed within a tooth, viz.: 

(i) The age and general condition of the patient. 

(2) The general condition of the pulp itself. 

(3) The amount and condition of the dentin intervening between the 

pulp proper and the application of the paste. 

(4) The climate or season of the year, strange as it may seem, influences 

the action of arsenic trioxid. 

Taking into consideration these various factors, the arsenical prep- 
aration should remain in the cavity from two to six days. At the 
second sitting the rubber dam should be adjusted, the teeth included 
sterilized, and the cement and paste removed, after which every surface 
of the cavity should be freshened with a large round bur. This not 
only insures the thorough removal of the arsenical paste, which, should 
a portion remain, is liable to produce pericemental inflammation, but 
it also mechanically sterilizes the cavity by removing the carious and 
infected dentin. This is important and is an aid in maintaining asep- 
sis in the removal of the pulp. In the author's judgment this is much 
better practice than to depend upon a solution of dialysed iron to neu- 
tralize the arsenic trioxid. 



METHODS. 329 

The pulp chamber can now be opened into and the pulp removed, 
observing practically the same details as explained under the anes- 
thetization method. Oftentimes in the initial opening into the pulp 
chamber, and sometimes on entering the canal, after the application 
of arsenic trioxid, the patient will experience some pain; but by gently 
working the broach up the side of the root, very little, if any, pain need 
be produced in removing the pulp, provided, of course, the tissue is 
devitalized. However, should pain be experienced, it is best to seal 
phenol or the modified phenol solution in the cavity in contact with the 
tissue from three to six days, when it can be removed without pain. 

In connection with the preservation of the color of the tooth, under 
the anesthetization method the author stated his objection to the use 
of hydrogen dioxid for removing the blood from the cavity and canal. 
It is necessary here also to refer briefly to a well-established practice of 
treating teeth after the pulps have been devitalized. It is the practice 
of many dentists, after removing the arsenical dressing, to flood the 
cavity with a solution of dialysed iron, after which the pulp chamber 
is opened into, usually producing some hemorrhage; then without any 
especial effort being made to remove the dialysed iron or blood, tannic 
acid in some form is sealed in contact with the pulp for a week or ten 
days, thinking it advantageous by this means to constringe and toughen 
the tissue before attempting its removal. Let us consider the rational- 
ism of such treatment. The pulp tissue in all large canals is sufficiently 
tough to be removed in its entirety, and it must be disorganized or 
removed piecemeal in small canals, whether it has been previously 
constringed or not. Hence, there is no advantage in using tannic 
acid and there is a serious objection. If those who follow this practice 
are observing, they will notice that after removing the tannic acid 
dressing, the pulp tissue is dark in appearance. They will also ob- 
serve that many teeth thus treated subsequently discolor. The cause 
for this is found in the fact that tannic acid and iron, in any form, are 
chemically incompatible, the resulting compound being iron tannate, 
one of the most insoluble substances known to chemistry. In the 
presence of moisture a form of ink is produced w T hich is a great staining 
agent for dentin, and one that is almost impossible to remove by any 
known process of bleaching. 

As has been stated elsewhere in this chapter, there are cases where, 
for want of time or other reasons, the pulp can be removed to advantage 
by devitalization; however, when this method is followed tannic acid 
should not be used, and every trace of dialysed iron (if used at all, and 
it is unnecessary to use it) and blood should be removed with alcohol 



330 THE ANESTHETIZATION AND DEVITALIZATION OF PULPS. 

or water. In those cases where we are certain that the pulp is all re- 
moved and where the canals can be thoroughly dried, the root filling 
can be inserted at the same sitting, provided there are no symptoms of 
pericementitis in the apical area. There are many good reasons, how- 
ever, for not filling the root at this time, some of w r hich have been 
considered under the anesthetization method. 

Complications. — In our discussion thus far of the methods of re- 
moving pulps from teeth, w r e have considered only favorable cases, 
selecting the method best adapted to the case at hand. There are many 
instances, however, where it is difficult to remove the pulp by either the 
anesthetization or devitalization method, at least until the tooth is 
placed in a more favorable condition. Oftentimes in approximating 
cavities the decay in one or both teeth has extended far beneath the gum, 
the rough gingival margin of the cavity acting as a slight irritant by 
which the gum tissue is stimulated, causing it to proliferate until it 
fills a portion of, and in some instances the entire, cavity. In such 
cases the first consideration is to dispose of the hypertrophied tissue. 
Where the gum fills only a portion of the cavity and the pulp of the 
tooth is not causing trouble, the cavity should first be enlarged and 
washed with a warm antiseptic solution, after w T hich it should be dried 
as well as possible and packed with warm gutta-percha. But in those 
cases w T here the gum tissue occupies the entire cavity, and especially 
where the tooth is aching, it should be removed at once. Hypertro- 
phied gum tissue is quite tough and fibrous, and if it is elevated or 
pushed back by means of a flat instrument, it wall usually be found 
that the attachment at the gingival margin is small and can easily be 
severed by employing gum scissors or a lancet, previously dipped in 
phenol. It is best not to tell the patient what you are going to do, for 
scarcely any pain will be experienced. The hemorrhage in these 
cases is usually profuse, but can readily be stopped by cauterization 
with 95 per cent phenol, a 50 per cent solution of phenolsulphonic 
acid, or a 15 per cent solution of trichloracetic acid. The blood should 
now be thoroughly removed, the cavity dried, moistened w r ith eucalyptol 
and packed with gutta-percha, letting it extend buccally and lingually 
to fill the interproximal space. The gutta-percha can be removed 
from the interior of the cavity with a heated flat instrument. Quite 
often the most practical way of adjusting the rubber dam in these 
cases is to place the clamp on the tooth posterior to the one thus packed, 
having a single hole in the dam include both teeth. The packing, 
if properly placed, will prevent leakage. The pulp can now be re- 
moved by the method which the operator deems the most feasible. 



METHODS. 331 

There is one instance in the removal of pulps from teeth, where 
students particularly are liable to make a serious mistake if they are not 
extremely careful. That is in cases where, in large occlusal cavities, 
especially in lower first molars of children, the pulp has died and the 
decay has extended through the bifurcation of the roots, leaving rough 
edges which continually irritate the tissue, causing it to proliferate 
and ultimately fill the cavity. To carelessly force the anesthetizing 
solution into such a cavity, where the pulp in the canals is putrescent, 
would be the means of causing an acute alveolar abscess. The applic- 
ation of arsenic trioxid would mean the loss of at least one tooth, 
perhaps one or two on either side of the one to which the application 
was made, with a portion of the alveolar process. 

Before applying either the anesthetizing or devitalizing agent a 
correct diagnosis should be made; we should ascertain definitely the 
kind of tissue in the cavity. With a little experience this is usually a 
simple matter. The history of the case as related by the patient will 
often serve as a guide. Pulp tissue is generally more sensitive than 
gum tissue, and when slightly pricked with a sharp instrument bleeds 
more profusely. If the tissue proves to be hypertrophied gum tissue 
it can be disposed of in the usual manner, the puncture closed tem- 
porarily with cement or gutta-percha and the tooth treated as the con- 
dition necessitates. When this cannot be accomplished, it is neces- 
sary to extract the tooth. In cases where the tissue is hypertrophied 
pulp tissue it will generally be found unusually resistant to both cocain 
hydrochlorid and arsenic trioxid, and it is sometimes necessary to 
resort to actual cautery by employing strong escharotics, such as pure 
phenolsulphonic acid, which is not -as painful here as would naturally 
be supposed, or to the administration of such general anesthetics as 
nitrous oxid in order to painlessly remove the tissue. 

Quite frequently we find cases where it seems almost impossible 
to force the anesthetizing solution through the dentin and into the 
pulp, and when arsenic trioxid is applied it has little or no effect. In 
these cases we can suspect that the pulp has receded because of some 
slight but continued external irritation and the space rilled in with sec- 
ondary dentin, the tubuli of which are irregular and do not run at 
right angles to the base upon which they rest, as in the normal dentin. 
This condition is more often found in elderly patients. As a result 
also of external irritation, pulp nodules, calcific bodies of various 
shapes, are sometimes found within the pulp itself. Many times in 
removing the pulp in these cases, the most painless and best results are 
obtained onlv bv a combination of both the anesthetization and de- 



332 THE ANESTHETIZATION AND DEVITALIZATION OF PULPS. 

vitalization methods; for the removal of these pulp nodules is often a 
difficult procedure. After we have used cocain hydrochlorid and 
pressure or previously applied arsenic trioxid and anesthetized or 
devitalized a portion of the pulp, we may be able to reach the pulp 
nodule or nodules without producing pain. But frequently these 
calcific bodies are agglutinated and close the mouth of the canal; 
especially is this condition found in molar teeth. The pulp tissue 
immediately under the nodule is extremely sensitive. In such a case 
the anesthetizing solution could not be forced into the canal without 
first removing the obstruction, and arsenic trioxid, if applied, would 
have no effect. These are cases which require much perseverance and 
patience on the part of both patient and operator. The nodule can 
sometimes be loosened by gently working around it with an exploring 
or other suitable instrument. The author has met with success by 
taking a small round bur and drilling past the nodule, care being taken 
not to puncture the root, then with the engine running rapidly the 
nodule is tapped and dislodged. When the obstruction in the pulp 
chamber and canals is removed the remaining tissue can be anesthe- 
tized or devitalized in the usual manner. If the devitalization method 
is employed the arsenical preparation can be placed over the mouth 
of the canal with safety; but it is never advisable to place the prepara- 
tion down in the canal. 

Arsenical Poisoning. — Before closing this chapter it may be well 
to consider the treatment of local poisoning by arsenic trioxid. How- 
ever, when such treatment is necessary it is due to carelessness on the 
part of the dentist or the patient, or both. It is never necessary to 
tell the patient what drug or remedy has been used in the treatment of 
teeth, many times it is advisable not to do so; but whenever an agent as 
destructive as arsenic trioxid is sealed within a tooth, the patient should 
be thoroughly impressed with the importance of keeping an appoint- 
ment, and of returning before the appointed time should any unto- 
ward symptoms develop. The patient should also be informed that 
the teeth thus treated might ache for a few hours, as they sometimes do, 
even when cocain is a constituent of the arsenical preparation; but 
that the aching will be of short duration. In case, however, the tooth 
or gum becomes sore, they should be instructed to return at once. 

In those cases where the arsenical preparation is not hermetically 
sealed within the tooth and some of it gets on the gum tissue, remaining 
only long enough to cause devitalization, all that is necessary is to 
first wash the part with an antiseptic solution, and then mechanically 
pick off the dead or sloughed tissue with sterile pliers until bleeding is 






METHODS. 2>33 

produced, if this is possible, after which the part should be disinfected 
and the tissue stimulated. To disinfect the part, any good disinfectant 
can be used. Nothing is better here than the official 3 per cent solu- 
tion of hydrogen dioxid. As a means of stimulating the cells, iodin 
compounds are useful. The Pharmacopeia recognizes a compound 
solution of iodin (5 per cent) which can be applied by first drying 
the part. After removing the dead tissue and disinfecting, the author 
prefers applying a paste made of europhen and oil of cloves. A pre- 
scription should also be written for an antiseptic mouth wash with 
which the patient should keep the mouth as clean as possible. The 
treatment can be repeated as often as the case necessitates; usually 
one or two treatments will suffice. 

In those severe cases where the arsenic trioxid has penetrated to 
and devitalized the process as well as the gum, the first treatment is 
surgical. After washing with an antiseptic solution, the affected proc- 
ess should be removed with a suitable bur in the engine. It may 
be necessary in extensive cases to extract the tooth, after which the 
treatment is practically the same as has been outlined above. Some- 
times there is pain following the surgical removal of the affected proc- 
ess. In this case orthoform can be added to the paste of europhen 
and oil of cloves. The case should be watched closely and the stim- 
ulating treatment kept up until the part has healed. The tissue in 
the interproximal space will never be fully reproduced, and will always 
be a source of more or less annoyance. 

It will be noted that in discussing the treatment of local arsenical 
poisoning, no mention has been made of dialysed iron. The practice 
of applying this agent to the affected part is both useless and wrong. 

In closing this chapter the author desires to emphasize what was 
stated in the beginning, that it is the plain duty of every practitioner 
to save the pulps of teeth in all cases where it can be done with any 
reasonable degree of success; yet experience and observation will soon 
show the folly of attempting to save a pulp that has been irritated for 
any great length of time, and will prove also that in these cases, the 
safest practice is to remove the pulp and subsequently fill the canals, 
notwithstanding the difficulty often attending the performance of this 
operation. 



CHAPTER XX. 
THE TREATMENT OF ORDINARY PERICEMENTITIS. 

BY J. P. BUCKLEY, PH. G., D. D. S. 

General Considerations. — It is not the intention to introduce in these 
chapters needless pathologic facts, yet in the treatment of pericemen- 
titis it is important to remember that the pericemental membrane is 
very vascular and well supplied with nerves; that it is enclosed within 
bony walls, and, therefore, when inflammation exists in the tissue the 
membrane becomes thickened, forcing the tooth from its socket. This 
elongation of the affected tooth is one of the chief symptoms of true 
pericementitis. 

Before discussing the therapeutics of pericementitis, I desire to 
indelibly impress upon the mind of the reader the fact that this con- 
dition is too frequently produced by carelessness on the part of dentists. 
It is not always possible to successfully perform dental operations 
without irritating the susceptible pericemental membrane; however, 
much of the trouble can be avoided if judgment is exercised and proper 
precautions are taken in treating teeth. 

There are at least two classes of irritants by which ordinary peri- 
cementitis is produced, viz. : 
(i) Drug irritants. 
(2) Mechanical irritants. 

The inflammation of the pericemental membrane caused from 
drug or mechanical irritants, will be called ordinary pericementitis 
in this chapter, in order to differentiate it from septic pericementitis 
— a condition produced by pathogenic bacteria, poisonous ptomains, 
and irritating gases, which have escaped from a putrescent root canal. 

Drug Irritants. — There are many circumstances and conditions 
which influence the action of drugs upon different individuals 
and upon the same individual under different conditions. We find 
cases occasionally where pulps have been removed by pressure anes- 
thesia, and where, seemingly at least, every precaution was taken in 
sterilizing the dentin, selecting a sterile anesthetizing solution and in 
applying the pressure; yet severe apical pericementitis follows. This 
may or may not be due to the drugs used in performing the operation. 
There are cases, too, where the pericemental membrane becomes 

335 



336 THE TREATMENT OE ORDINARY PERICEMENTITIS. 

highly inflamed and extremely responsive from the action of arsenic 
trioxidj even when the drug was properly sealed within the tooth only 
a short time. These are conditions over which the operator seems to 
have no control; however, drugs are often used injudiciously. In the 
preceding chapter it was stated that an anodyne treatment was in- 
dicated after the mechanical or surgical removal of the pulp. There- 
fore, care should be taken to select drugs for this purpose which produce 
a soothing and not an irritating effect. There are some instances 
in dental practice where we desire to irritate and thereby stimulate the 
pericemental membrane; but this should be avoided here. Judgment 
should also be exercised in sealing in anodyne remedies, such as phenol, 
oil of cloves, etc., in the canals, especially in bicuspid and molar teeth, 
for should the temporary filling be left too full and the remedy forced 
through the apex by the closing of the jaws, even these agents cease to be 
anodynes and become irritants. Whether phenol, oil of cloves, and 
similar drugs or remedies are anodynes or irritants, depends largely, 
then, on where and how they are used. 

In filling root canals it is the practice of many dentists — the author 
among the number — to moisten the canals with eucalyptol before in- 
troducing chloro-percha and the gutta-percha cone. Care must be 
taken here to use eucalyptol and not oil of eucalyptus, unless 
it be the refined product. Commercial oil of eucalyptus has been 
the cause of many cases of apical pericementitis following the 
most careful filling of root canals. The eucalyptus tree produces a 
volatile oil which contains three constituents, each distilling over at 
different temperatures; the first product thus obtained is eucalyptol, 
hence the most volatile constituent of oil of eucalyptus and the one 
which is the solvent for gutta-percha. While eucalyptol is a slight 
irritant, it is not nearly so irritating as oil of eucalyptus. The irritat- 
ing property of eucalyptol can be modified and its antiseptic value in- 
creased by adding menthol and thymol in the following proportion: 

1$ — Menthol, gr. ij 

Thymol, gr. iij 

Eucalyptol, f . 5 j — M. 

Sig. — Use as directed. 

This remedy is equally as good a solvent for gutta-percha as is eucalyp- 
tol alone; and will be called modified eucalyptol in the following chap- 
ters. 

Mechanical Irritants. — The pericemental membrane is frequently, 
I might add too frequently, irritated by mechanical irritants, such as 
root canal fillings, ill-fitting partial plates, crowns and bridges, mallet- 



GENERAL CONSIDERATIONS. 337 

ing, regulating, faulty occlusion, salivary and serumal calculus, etc. 
There is perhaps more pericementitis produced by root canal fillings 
than by any other mechanical irritant. In filling root canals we 
should be absolutely certain that the canal is aseptic. If there be any 
doubt as to this, the operation should be deferred. In a subsequent 
chapter the author will discuss in detail the technique of filling root canals ; 
however it is well to mention here that care should be taken in filling 
all large canals so that the filling material may not be forced through 
the apex of the root; especially should we be careful in filling the canals 
of teeth after having treated an alveolar abscess. In these cases we 
must not expect the patient to flinch in filling the root, for there is no 
live tissue at the immediate end. The apex has been enlarged and it 
is very easy to force the filling material through into the space where the 
tissue has been destroyed. When granulation fills this space and the 
newly formed tissue comes in contact with the foreign material, the 
result will be a "lame tooth," which means pericemental trouble. 

A frequent cause of pericementitis is the presence of microorgan- 
isms, which have been introduced through the failure to establish and 
maintain sepsis in removing the pulp tissue; or pathogenic bacteria, 
poisonous ptomains and irritating gases that have escaped into the 
apical area from a putrescent root canal. This particular kind of 
pericementitis is known as septic pericementitis, and is closely associated 
with incipient abscess. The nature of the irritants and the treatment 
of the condition will be fully considered in a subsequent chapter. 

Therapeutics. — The first step in the treatment of ordinary peric- 
ementitis is to adopt the surgical principle of ascertaining the cause 
and removing or correcting it, if at all possible. In the earlier stages 
of pericemental inflammation, it is not always an easy matter to ascer- 
tain the true cause of the disturbance. For instance, in those cases 
following the removal of the pulp tissue, it is difficult to know whether 
the cause is the root filling, the medicine used in the treatment, or 
whether we failed to establish and maintain asepsis in performing the 
operation. The author is inclined to believe that it is more frequently 
the latter than most operators are willing to admit; for certain it is 
that the more nearly we approach absolute asepsis in these operations, 
the less pericemental trouble we will have. The teeth thus affected 
are extremely sore, and any remedy can be used in the treatment that 
will give immediate relief. This is what the patient most desires, 
and, too often it appears, it is that which the dentist fails to give. Both 
local and general remedies can be employed. General remedies are 
more valuable in the treatment of septic pericementitis. If they are 



338 THE TREATMENT OF ORDINARY PERICEMENTITIS. 

used at all in treating ordinary pericementitis, they should be used only 
in cases where the patient is nervous and has lost considerable sleep. 
For immediate relief we must depend largely upon the local applica- 
tion of drugs and remedies. In those cases following the removal of 
the pulp by either the anesthetization or devitalization method, and 
where the canals have not been rilled, the pain can be relieved almost 
instantly by the following method: Adjust the rubber dam. If it 
is necessary to use a clamp, it should be placed on the tooth posterior 
to the one affected. Sterilize the teeth included in the dam and re- 
move the dressing from the canals. Dehydrate the tooth structure 
with absolute alcohol. Then wrap cotton loosely around a smooth, 
sterile broach, dip in oil of cloves or eugenol, and carefully work in each 
canal. Remove the broach, leaving the cotton. Heat should now 
be applied to the remedy by means of a hot air instrument or a chip- 
blower until the cotton becomes dry. Repeat this process several 
times, after which the same remedy should be carefully sealed within 
the canal. In doing this, w r e not only get the benefit of the heat, which 
is valuable; but the eugenol, the constituent of cloves, is driven into 
the tooth structure, producing a profound anodyne effect upon the 
sensitive membrane. The author has succeeded in giving immediate 
relief by this method of treatment when many others have failed. 
Grinding the cusps of the tooth where it can be done without injury is 
advisable; a counterirritant can be applied to the gum and the patient 
dismissed for several days. It is scarcely necessary to instruct the 
patient to favor the tooth. 

In the treatment of pericementitis following the filling of the root, 
having every reason for believing that the canals w r ere aseptic, one of 
the last things the author would suggest doing would be to attempt to 
remove the root filling. Usually this only serves to further aggravate 
the condition. These cases can best be treated by counterirritation 
and general remedies. By counterirritation is meant the application of 
an irritant to some normal part of the body for the purpose of influenc- 
ing favorably some other part, usually deep-seated, which is diseased. 
This irritant is generally applied to the gum over the affected tooth. 
Capsicum plasters, black mustard papers, cantharidal collodion, all 
official preparations, are valuable; or the following liniments, which are 
more generally used, give much relief: 

1^ — Menthol, gr. xx 

Chloroformi, f. 3 j 

Tincturae aconiti, q. s. ad, f. § j — M. 

Sig. — Dry the gum and apply freely over the af- 
fected tooth for several minutes. 



GENERAL CONSIDERATIONS. 339 

fy— Tincturae aconiti, f . 5 ij 

Tincturae iodi, 

Chloroformi, aa f. 5 j — M. 

. Sig. — Make one application to the gum as above. 

1$ — Liquoris iodi composite, f. 5 j 

Sig. — Use as above. 

Inasmuch as tincture of aconite is an important ingredient in many 
liniments used in the local treatment of pericementitis and facial neu- 
ralgia, it is well to remember that the United States Pharmacopeia of 
1900 reduced the strength of this preparation from 35 per cent to 10 
per cent. Therefore the new tincture can be employed more freely in 
these cases without danger of poisoning. 

As a remedy to be applied by the patient at home, a split raisin, 
soaked in hot water, and on which is dusted red pepper, can be held on 
the gum over the affected tooth. A very efficacious remedy is to di- 
rect hot water with some force on the part, beginning with warm water 
and increasing the heat gradually until it is nearly boiling. This must 
be kept up until we get the full benefit of the heat and resolution pro- 
moted. Another good remedy to have the patient employ, is the hot 
foot bath. The value of this remedy, like the application of hot water 
to the gums, depends largely upon the manner in which it is done. A 
deep foot-bath tub should be used and the temperature of the water 
gradually increased until it is as hot as can be borne. This should 
be continued from twenty to thirty minutes. 

There r re many other drugs and remedies which can be employed 
in the local treatment of this condition. Those which have been men- 
tioned here the author has found valuable in his practice. It is far 
better to have a practical knowledge of a few remedies than a super- 
ficial knowledge of many. The general remedies to be administered 
in the treatment of ordinary pericementitis, if found necessary, will be 
discussed under the treatment of septic pericementitis and incipient 
abscess in a subsequent chapter. 



CHAPTER XXI. 
THE CHEMISTRY OF PULP DECOMPOSITION. 

BY J. P. BUCKLEY, PH.G., D. D. S. 

General Considerations. — The subject of pulp decomposition is 
one that has commanded the attention of many investigators in our pro 
fession, and at the present time the conclusions as to the chemistry of 
the process are by no means uniform. While this fact is to be regretted, 
it must be remembered here that there are many difficulties presenting 
themselves to the student who attempts to study this complicated proc- 
ess from the chemical viewpoint, either for the purpose of outlining a 
rational treatment for the correction of the putrescent condition, or for 
the purpose of solving the knotty problems of the discoloration of tooth 
structure from this source. Until we comprehend more fully the nature 
of the chemical reactions taking place in the splitting up of the com- 
plex bodies of dead pulp tissue and have a more definite knowledge 
of the intermediate and end-products thus produced, the application 
of drugs and remedies for the correction of the putrescent condition 
and for the restoration of the color of the tooth structure can never be 
placed upon a rational basis, but must be empirical, as it has been in 
the past. This is not in accordance with the tendency of the present 
time. There is a strenuous effort being made in both medicine and 
dentistry, to rid the professions of much of the empiricism of the past 
and to place the treatment of all diseased conditions upon a rational 
basis. With this end in view the author desires in this chapter to 
direct the reader's attention to the chemistry of pulp decomposition. 

It is essential in studying the chemistry of this process to first as- 
certain the chemical constituents of the original pulp tissue. So far as 
chemists have been able to determine, practically all of the elements 
are present in the pulp tissue and its vascular supply that are found in 
any other animal tissue. These elements are arranged in different 
compounds which make up the pulp tissue, the proportion of which 
varies from other tissues, and this, no doubt, accounts for the histologic 
difference between this and many of the other tissues of the body. 
However, from a general chemical examination of the pulp tissue we 
find it analogous, or nearly so, to all other animal tissue. This suggests 

34i 



342 THE CHEMISTRY OF PULP DECOMPOSITION. 

at once the necessity for the student's familiarity with the general 
composition of animal tissue, which will now be considered. 

Chemical Composition of Animal Tissue. — There are at the present 
time about seventy-six elements known to chemistry; but of this num- 
ber less than seventeen unite, in varying proportions, to form the chem- 
ical basis of the animal body. In fact, six elements are about all 
with which we are concerned in the study of the decomposition of the 
pulp tissue. These elements are carbon, C; hydrogen, H; oxygen, O; 
nitrogen, N; sulphur, S; and iron, Fe. 

For convenience in study, the various substances found in animal 
tissue are divided into two general classes, the classification being based 
upon the presence or absence of the element nitrogen, and are accord- 
ingly called nitrogenous and non-nitrogenous substances. 

Nitrogenous Substances. — We are taught by physiologists that 
nitrogenous organic bodies take the chief part in forming the solid 
tissues, and to an extent are also found in the fluids of the body. Pro- 
teid, or albuminous, substances are the principal nitrogenous com- 
pounds, and one or more enter as an essential part into the formation 
of all living tissue. The elements which constitute the proteid mole- 
cule are carbon, hydrogen, oxygen, nitrogen and a small amount of 
sulphur. Iron and phosphorus are knowm to exist in the molecule of 
some proteid bodies. While some chemists have attempted to con- 
struct a formula for the molecule, none has been accepted as correct, 
the opinions of investigators being so varied. To the casual observer 
it may seem strange that a molecule consisting largely, as it does, of 
carbon, hydrogen, oxygen and nitrogen, should have these four simple 
elements so arranged as to baffle chemists in their effort to construct a 
rational formula. But this difficulty is readily explained by the fact 
that of all the elements none differ more widely from each other in 
their physical and chemical properties than these four. Carbon is a 
solid substance which exists in nature in three forms: Charcoal, 
graphite, and diamond, and can scarcely be fused or volatilized. Hy- 
drogen, oxygen, and nitrogen are colorless gases which cannot be 
solidified by any known means and can be converted into liquids only 
with difficulty. The three gases also differ in their chemical activity. 
Hydrogen is combustible; oxygen will not burn, but will support com- 
bustion; while nitrogen is perfectly indifferent. Fortunately, too, for 
nature, in her effort to arrange these elements into a complex molecule, 
the valency of each differs. Hydrogen is univalent, oxygen bivalent, 
nitrogen trivalent, and carbon quadrivalent, generally considered. 
Carbon atoms have also, to a higher degree than the atoms of any other 



GENERAL CONSIDERATIONS. 343 

element, the power of combining with each other by means of a portion 
of the affinity possessed by each atom, thereby increasing the possibil- 
ities of the formation of complex compounds. Thus many atoms of 
the same element occur in each molecule, which, together with the fact 
that one of the elements is that peculiar, undecided and indifferent 
element, nitrogen, aids materially in explaining the reason for the insta- 
bility of the proteid molecule, or the ease with which under certain 
conditions it is decomposed. 

In order that the reader may be able to follow a theory which the 
author will advance in a subsequent chapter on the discoloration prob- 
lem, it is well to remember here that the relative amount of nitrogen 
compared with sulphur found in the proteid molecule is 15 per cent of 
the former to 0.3 per cent of the latter. 

Non-nitrogenous Substances. — The non- nitrogenous substances con- 
sist of carbohydrates and fats. Several classes of carbohydrates are 
known to exist, all of which are much less complex than the proteid 
group; and the arrangement of the atoms in the molecule is much better 
understood. The carbohydrate molecule is composed of three ele- 
ments — carbon, hydrogen and oxygen. There are always six (or a 
multiple of six) atoms of carbon in the molecule, while the hydrogen 
and oxygen exist in the proportion to form water. These compounds 
readily undergo the process of fermentation. 

Human fats are principally mixtures of palmitin, C 3 H 5 (C l6 H 3I 0) 3 - 
3 ; stearin, C 3 H s (C l8 H 35 0) 3 3 ; and a small amount of olein, C 3 H 5 - 
(C l8 H 33 0) 3 3 . As shown by the formula of these compounds, the 
molecules of each also consist of carbon, hydrogen and oxygen. The 
proportion of these elements varies in the different compounds. That 
fats are decomposed or saponified by alkalies, or ferment in an alkaline 
medium, should be remembered, both in the treatment and the bleach- 
ing of teeth. 

Thus we have every reason for believing that the pulp tissue, like 
nearly all living organic tissue, is composed of proteids, carbohydrates, 
and fats; and on this hypothesis the author will endeavor to ascertain 
the intermediate and end-products resulting from the decomposition 
of this tissue when death occurs. Before doing so, however, it may be 
well that the reader fully understand what is meant by the terms fer- 
mentation and putrefaction. These terms are applied to peculiar kinds 
of decomposition by which the molecules of certain organic substances 
are broken up into simpler compounds. The difference between the 
terms is that fermentation is applied to the decomposition of those 
substances which belong to the group of carbohydrates, while putre- 



344 THE CHEMISTRY OF PULP DECOMPOSITION. 

faction is applied to the decomposition of those substances which prop- 
erly belong to the proteid group and are classified as nitrogenous sub- 
stances. 

Pulp Decomposition. — The decomposition of the pulp tissue is 
essentially an analytic process which takes place gradually. Con- 
ditions being favorable, the germs present first act upon the complex 
and unstable substances composing the original tissue, splitting them 
up into less complex compounds, many of which are capable of further 
analysis; and the process goes on until simple and well-known com- 
pounds are the result. For convenience in studying this subject the 
compounds resulting from this analytic process will be arbitrarily 
divided into two classes, intermediate and end-products; and it will be 
seen that it is largely the products of putrefaction rather than of fer- 
mentation with which we have to contend in the correction of the pu- 
trescent condition. 

Intermediate Products. — The intermediate products depend to an 
extent upon the character of the microorganisms in the tissue, but it is 
safe to say that certain ptomains and amido-acids are formed. 

(i) Ptomains. — Ptomains are nitrogenous compounds of organic 
origin, having the reaction and basic property of alkalies. By some 
authorities they are called animal alkaloids, to distinguish them from a 
similar group of organic bases knowm as vegetable alkaloids. 

Among the ptomains liable to be produced are putrescin, C 4 H I2 N 2 , 
cadaverin and neuridin, C 5 H I4 N 2 , the last two named being isomeric 
as shown by the formula. One of these ptomains, neuridin, is non- 
infectious; therefore its presence is of little importance other than to 
know that it is a nitrogenous base from which ammonia, NH 3 , or 
derivations of ammonia, is evolved by further putrefaction. Still, 
according to Yaughan and Novy, while pure neuridin is non-poison- 
ous, it possesses a toxic property as long as it is contaminated with 
other poisonous products of putrefaction. This holds true for all non- 
poisonous bases. Insofar as the correction of the putrescent condition 
is concerned, putrescin and cadaverin are perhaps the most important 
intermediate products known to be formed in the splitting up of the 
proteid molecule. Like neuridin, they are basic nitrogenous com- 
pounds, capable of undergoing further putrefaction, evolving ammonia 
or derivatives; but unlike this compound, while they were at first re- 
garded as physiologically inactive, both of these bases have been proved 
by Scheurlen, Grawitz and others to be capable of producing inflamma- 
tion and suppuration. Therefore if by instrumentation or other- 



GENERAL CONSIDERATIONS. 345 

wise they are forced through the apices of the roots, septic pericemen- 
titis or perhaps on acute alveolar abscess will result. 

(2) Amido-acids. — Amido-acids are acids in which hydrogen has 
been replaced by the univalent radical, NH 2 . Among the amido- 
acids formed in pulp decomposition, in all probability, are tyrosin, 
C 6 H 4 OHC 2 H 3 (NH 2 )C0 2 H, and leucin, C 5 H IO NH 2 C0 2 H. These 
substances, wherever found, have practically the same physiologic 
properties and pathologic significance. They occur in the intestine 
during the digestion of proteids, and leucin is found in almost every 
cell of the animal body.* Pathologically, they are found in ather- 
omatous cysts, in pus, abscesses, etc., as well as in a putrescent root 
canal. It is well to remember here that these intermediate products 
are also nitrogenous compounds from w T hich ammonia, or derivatives 
of ammonia, is evolved by further putrefaction, and that fats are one of 
the end-products. 

End-products. — The chief end-products of pulp decomposition, 
as has been known for a long time, are water, H 2 0; carbon dioxid, 
C0 2 ; acetic acid, HC 2 H 3 2 ; ammonia, NH 3 ; hydrogen sulphid, 
H 2 S; and a semi-putrid substance consisting largely of fats, depending 
upon the extent to which the putrefactive process has progressed. 

Simultaneously with the decomposition of the pulp tissue proper, 
the dentinal fibrillar are broken up, as is also the hemoglobin and other 
constituents of the blood; and the tubuli as well as the pulp chamber 
and root canals are filled with the intermediate and end-products 
of the decomposition. 

The principal gases generated by the putrefaction of the proteid 
substances, the main constituent of the original pulp tissue, are ammo- 
nia and hydrogen sulphid. Now, it is interesting and important to 
know which of these two gases is evolved in the greater quantity. This 
is easily estimated when we recall the relative amount of nitrogen and 
sulphur found in the proteid molecule.. As previously stated, there is 
approximately 15 per cent of the nitrogen to 0.3 per cent of sulphur. 
Hence, ammonia is evolved in the greater quantity. It is quite evident, 
then, that hydrogen sulphid is not generated in a putrescent root canal 
in such quantities as has been so generally supposed; yet this com- 
pound is a constant end-product and is important, because it is an acid 
gas, with a disagreeable odor, having local irritating properties; and 
also because of the part it plays in the discoloration of the tooth struc- 
ture. The author desires to state here, however, that while he realizes 
hydrogen sulphid is an active chemical agent, in his opinion it has been 

* Simon's "Manual of Chemistry. 



346 THE CHEMISTRY OF PULP DECOMPOSITION. 

greatly over-estimated in the role it assumes in the discoloration of teeth 
from pulp decomposition as will be shown in a subsequent chapter. 

In our study thus far of the chemistry of the complicated process 
of pulp decomposition, we have learned something of the nature of 
the intermediate and end-products resulting therefrom, and now it is 
possible for us to select, with some intelligence, drugs and remedies 
which will not only destroy bacteria, but will also act chemically upon 
these noxious products, converting them into non-infectious and non- 
toxic compounds. 



CHAPTER XXII. 

THE TREATMENT OE PUTRESCENT PULPS— ACUTE 
AND CHRONIC ALVEOLAR ABSCESS, WITH COM- 
PLICATIONS; AND THE FILLING OF 
ROOT CANALS. 

BY J. P. BUCKLEY, PH. G., D. D. S. 

General Considerations. — The treatment of putrescent pulps and 
their sequelae in the past, has, to a great extent, been purely empirical. 
The reason for this can be found in the apparent lack of interest which 
generally has been shown in the chemistry of pulp decomposition. A 
knowledge of the changes wrought in the splitting up of the complex 
bodies of the dental pulp by microorganisms is of vital interest to 
every practicing dentist; and every student should therefore familiar- 
ize himself with this important subject. The only method by which 
drugs and remedies can be scientifically applied to the treatment of 
the conditions under consideration is to have a definite knowledge 
of the intermediate and end-products resulting from the putrefactive 
process as outlined in the preceding chapter. 

Every practitioner of- dentistry knew from sad, past experience 
•:hat in the process of pulp decomposition, some kind of mephitic gases 
were evolved which if confined would produce severe pathologic 
disturbances; but just what the gases were and how the unfavorable 
conditions were brought about we were left to conjecture. From our 
study of the chemistry of pulp decomposition we have every reason 
for believing that the main gases produced are ammonia and hydrogen 
sulphid. When these gases are generated and cannot readily escape 
through a cavity, pressure is produced, thereby forcing the poisonous 
otomains through the apices of the roots into the surrounding tissue 
from which infection, septic pericementitis and in many instances an 
alveolar abscess result. 

There has been much discussion in the dental literature of the past 
in regard to the penetrating or non-penetrating power of coagulating 
agents in putrescent root canals. It is true, as claimed by some 
authorities, that such drugs as phenol, creosote, solutions of zinc chlorid, 
etc., are contraindicated in the treatment of putrescent pulps, but not 

347 



348 THE TREATMENT OF PUTRESCENT PULPS. 

because they possess the coagulating property; for when the dental 
pulp is undergoing or has undergone the process of decomposition, 
the proteid constituents or coagulable substances have lost their for- 
mer identity, and new compounds with entirely different properties 
have been formed. In selecting drugs to be used in the treatment of 
this condition, the author will therefore eliminate the question of coag- 
ulation and will select drugs, which if properly used, will unite chemic- 
ally with the intermediate and end-products of decomposition, con- 
verting them into odorless and non-infectious compounds, as well 
as destroy germ life. In this connection it should be remembered 
that the putrescent condition has been brought about through the 
agency of microorganisms by a gradual analytic process, and among 
the products formed which must be considered in the treatment are 
hydrogen sulphid, the poisonous ptomains (putrescin and cadaverin), 
and ammonia or derivatives, the latter gas being evolved from the further 
putrefaction of the last named compounds, or compounds of similar 
composition. It is well to remember also that fats or fatty acids are 
a class of end-products resulting from the putrefaction of proteid 
substances. 

The main gases formed, then, are ammonia and hydrogen sulphid. 
Now it will be necessary to dispose of these gases in order to hermetic- 
ally seal the cavity, an object the accomplishment of which is much 
desired in the treatment of these cases; for by so doing we prevent the 
oral fluids from contaminating the medicine within the tooth, the med- 
icine from escaping into the patient's mouth, and the tooth from 
changing color during the time of treatment. 

It has been known for some time that formaldehyd (CH 2 0), a gas 
which occurs in commerce in a thirty-seven per cent aqueous solution 
and which solution is recognized by the United States Pharmacopeia 
of 1900 under the name of liquor formaldehyd, or formalin, will 
unite with ammonia, producing urotropin, a solid, as 6CH 2 0+4NH 3 
= (CH 2 ) 6 N 4 + 6H 2 0. 

Formaldehyd unites also with hydrogen sulphid, forming, in the 
author's opinion, methyl alcohol, a liquid, and sulphur, a solid, as 
2 CH 2 0+2H 2 S = 2CH 3 OH + S 2 . 

It is stated on good authority that this same gas, formaldehyd, 
united with basic ptomains, forms inodorous compounds. By the 
use of formaldehyd, then the irritating gases and poisonous liquids 
(largely ptomains) can be changed chemically into non-irritating and 
non-poisonous liquids and solids. The official solution of formaldehyd, 
however, is too irritating for general use; therefore, inasmuch as fats 



GENERAL CONSIDERATIONS. 349 

result from pulp decomposition and are present as such in a putres- 
cent root canal, the author selected cresol as an agent with which to 
dilute the official solution and thereby modify the irritating action of 
formaldehyd. Cresol is now also recognized by the United States 
Pharmacopeia of 1900 under this name. Formerly the product was 
commercially called tricresol. This agent has a tendency to darken 
when exposed to light. It is recommended that a clear solution be 
obtained and then kept in an amber colored bottle. 

Liquor formaldehyd can be diluted with such other agents as 
phenol, or creosote, if, in the latter instance, a small amount of alcohol 
is added to clear the solution. Cresol, however, is recommended for 
four principal reasons: 

1. It is miscible with the liquor formaldehyd in all proportions, 
thus making, without the addition of alcohol, a good pharmacal product 
from which formaldehyd gas is constantly generated. 

2. It is a good disinfectant, much more powerful than phenol. 

3. It possesses an anodyne property which modifies the irritating 
action of formaldehyd. 

4. It acts chemically upon the fatty compounds thereby disposing 
to advantage of these substances. 

Treatment. — In the successful treatment of the conditions under 
consideration there are three important factors which must be ac- 
complished : 

1. Establish asepsis. 

2. Prevent recurring sepsis. 

3. Preserve or restore the color of the tooth. 

I. Putrescent Pulps. — In calling the attention of the reader to a 
method of treating this condition, which has proved very successful 
in the author's practice, I desire to emphasize the necessity for ob- 
serving the details of the method. Our first duty here, as in all treat- 
ment cases, is to make a correct diagnosis, after which the rubber 
dam should be adjusted in every case where it is possible to do so, 
and all the teeth included, sterilized. For this purpose either a ten 
per cent solution of formaldehyd to which a small amount of borax 
has been added, or a 1-500 solution of mercury bichlorid in cinnamon 
water can be used. After using one of these solutions the teeth are 
bathed in alcohol, when, with a suitable round bur, the pulp chamber 
is freely opened, exposing all of the canals, but making no attempt 
to remove the contents therein at this sitting. Now, on a small pled- 
get of cotton the following remedy is placed in the pulp chamber and 
over the mouth of each canal. 



350 THE TREATMENT OF PUTRESCENT PULPS. 

Original Formula. 

K — Cresolis, 

Liquoris formaldehydi, aa f 5j — M. 

Sig. — Use as directed. 

For convenience this remedy will be called formocresol. It is 
always best to seal the cavity with a quick-setting cement, for the 
remedy should be hermetically sealed and pressure must be avoided. 
To prevent the cement from rilling the entire cavity and also to facili- 
tate its subsequent removal, metallic or paper discs or even cotton can 
be placed over the remedy, filling most of the cavity, when only a veneer 
of cement is necessary to hermetically seal it. This dressing can re- 
main until you wish to have the patient return for a subsequent sitting. 
The author prefers to leave it about two or three days. However, it 
can be safely changed the following day, and no harm follow if it 
remains a week or more. At the second sitting, the rubber dam 
should be adjusted, the teeth included sterilized, and the dressing 
removed, after which the canals should be mechanically cleaned with 
a proper broach, exercising the same judgment here in the selection 
of the broach as was emphasized in a previous chapter. If there be 
any odor in the canals characteristic of putrescence, or if effervescence 
is produced by testing with a solution of hydrogen dioxid, the canals 
should be dehydrated with alcohol and warm air as thoroughly as 
possible and the original formula again placed on cotton, this time 
loosely in each canal, and the cavity hermetically sealed. 

In those cases, where, at the second sitting, there is no evidence 
of putrescence, which will be found to be the condition generally if 
the first treatment is properly employed, the original formula can be 
modified and used. It is not necessary or advisable, however, to 
keep a modified formula prepared. It can readily be made at the 
time by taking two minims of the original formula on a clean watch 
crystal, and adding to this one or two minims of cresol as thought best 
by the operator at the time. This dressing should remain for at least 
three days, by which time the remedy will have sterilized the entire 
tubular structure of the dentin, thus establishing asepsis. All that is 
necessary now to prevent recurring sepsis is to thoroughly fill the canals. 
This remedy will not discolor tooth structure and the fact that it not 
only can but should be hermetically sealed in the cavity, will prevent 
discoloration by the ingress of the fluids of the mouth. In case the 
color of the tooth crown was lost before undertaking the treatment and 
being desirous of preserving the tooth by an inlay or filling, the color 
can be restored by one or two applications of sodium dioxid, Na 2 2 . 



GENERAL CONSIDERATIONS. 35 I 

The use of this agent will be explained in a subsequent chapter on 
bleaching teeth. 

Complications. — i. Badly Decayed Root. — This formocresol is 
very destructive to the soft tissues of the mouth, therefore the im- 
portance of always adjusting the rubber dam. If this cannot be done 
on account of a badly decayed root, it is suggested that care be taken 
in sealing the remedy in the cavity at the first sitting, and, in placing 
the cement, the original outline of the root can be approximated. 
After the cement has set, a band or matrix of gold or German silver 
can be fitted to and cemented on the root. In treating the case where 
there is a tooth posterior, it is best to place the clamp on this tooth 
and gently stretch the rubber over the band and thereby avoid 
loosening it. 

2. Pulp Partially Alive. — In those cases where the pulp tissue 
is putrescent in one or more canals of a multirooted tooth and alive 
in the other one or two canals, as the case may be, we will find much 
satisfaction in using the formocresol remedy. These are exceptional 
cases and it is difficult to know whether this condition exists until the 
second sitting. If there be much vitality in the live pulp tissue, the 
formaldehyd in the remedy will doubtless make the tooth ache, but 
after we know the conditions our method of procedure is simple and 
the results will be certain. A small pledget of cotton dipped in the 
remedy can be gently placed over the mouth of the canals which con- 
tain putrescent material, and a thin quick-setting cement flowed over 
the cotton. After the cement has set the live pulp tissue in the remain- 
ing canals can be anesthetized or devitalized as the operator deems best 
at the time. Formerly these were difficult cases to treat, but with a 
remedy which can be hermetically sealed in a putrescent root canal, 
the procedure is materially simplified. 

The author realizes that the method of treating putrescent pulps, 
here given, is a radical departure from those generally advocated; and, 
like myself, at first some of my experienced readers may hesitate to 
hermetically seal a cavity in a tooth which contains a putrescent pulp. 
The reason this could not be done in the past by the methods in vogue, 
is that drugs, in most instances, were selected and used solely because 
of their ability to inhibit the growth or destroy the vitality of micro- 
organisms. The fact that there were other things, such as irritating 
gases, and poisonous ptomains, found in the canal and tubular structure 
of the dentin, and also the further fact that it was as necessary to dispose 
of these substances as it was to destroy germ life, was not given the 
significance this phase of the subject merited. The treatment which 



353 THE TREATMENT OF PUTRESCENT PULPS. 

is here outlined is along rational lines, for the remedy chemically 
converts the noxious intermediate and end-products of pulp decom- 
position into substances which themselves possess antiseptic and dis- 
infectant properties. 

II. Acute Alveolar Abscess. — The treatment of septic peric- 
ementitis and acute alveolar abscess, as was intimated in the chapter 
on The Treatment of Pericementitis, is so nearly identical that 
they will be discussed here conjointly. In those cases where the 
patient did not present for treatment until the confined gases had 
escaped through the end of the root, carrying the poisonous ptomains 
into the surrounding tissue, it is our duty to try -to aid nature in abort- 
ing an abscess. It is in these cases that good judgment must be exer- 
cised, and extreme care taken. There is no condition which we are 
called upon to treat wherein a practical knowledge of pathology and 
therapeutics will serve us better than in this particular case. Fre- 
quently patients delay coming to the dentist until the infection has pro- 
gressed to a point where all remedies will fail in aborting an abscess; 
but in many instances this result may be prevented by the proper 
use of drugs. The local treatment here is exactly the same as above 
for an ordinary putrescent pulp; for you never have a case of septic 
pericementitis or incipient abscess unless the pulp is dead and has 
undergone, partially at least, the process of decomposition. How- 
ever, if the tooth is extremely sore, as is usually the case, the patient 
need not be subjected at this sitting to the annoyance of adjusting the 
rubber dam. Keep the tooth just as dry as possible, open into the 
pulp chamber, holding the tooth by some means, while drilling, so 
that the jarring will not further irritate the condition; then carefully 
seal in the formocresol remedy with cement; after which our attention, 
if necessary, should be given to the treatment of the infected peri- 
cemental membrane. In order to control the infection, and at the 
same time aid nature in readjusting the abnormal condition, it is not 
only our privilege, but it is our duty in these severe cases to administer 
internal drugs. Here alterative drugs are indicated. The great rep- 
resentative of the alterative class is potassium iodid, which can be 
given in the following prescription: 

1$ — Potassii iodidi, 5 jss 

Syrupi sarsaparillae comp., fo iij — M. 

Sig. — Take a teaspoonful in water after meals. 

Ordinarily the directions would be as given, to have the patient 
take a teaspoonful three times a day after meals; but in these days of 
septic pericementitis or incipient abscess it is best to direct the patient 



GENERAL CONSIDERATIONS. 353 

to take a teaspoonful every two hours until three or four doses are 
taken, and then follow the directions written on the label. It is well 
also to avoid the accumulation of blood in the part. To prevent this, 
saline cathartics are indicated — one that can be given is the official 
solution of magnesium citrate, owing to the facility with which it can 
be taken and its acceptability to the stomach, a prescription for which 
follows : 

f£ — Liquoris magnesii citratis, f o xij 

Sig. — Take one-half at once and the other half in two 
hours, if necessary. 

Magnesium sulphate (Epsom salts) is also an excellent remedy to be 
used for this latter purpose. The patient can be directed to take 
a teaspoonful dissolved in a wine-glassful of warm water, having a 
glass of cold drinking water at hand to drink at once after taking the 
strong salt solution. The cold water removes at once the bitter and 
unpleasant taste of the salt. A very good remedy to have the patient 
employ at home is the hot foot bath as explained in the chapter on The 
Treatment of Pericementitis. In malarial regions and in the spring of 
the year in many localities, the salts of quinin can be given, with bene- 
ficial results. The salt which the author prefers giving, if indicated 
in the conditions under consideration, is quinin bisulphate. Nearly 
all pharmacies have the salts of quinin put up in the form of pills. 
While these pills may be given it is much better to write a prescription 
for capsules. The gelatin capsule is soon dissolved in the stomach; 
thus we obtain the action of the drug more rapidly than when given 
in the dry, hard, pilular form. The following prescription can be 
written for the drug in two grain doses: 

1$ — Quininae bisulphatis, gr. xxiv 

Ft. capsular No. 12. 
Sig. — Take one capsule every hour until the effect become 
noticeable. 

Quinin acts differently upon different individuals. Most adult pa- 
tients know the effect of this drug upon their system and therefore 
will be able to aid the dentist in determining the amount to be taken 
in a given case. 

One of the most prominent symptoms with which we have to 
contend here is pain. In most cases the pain will subside soon after 
the local treatment; however, it is necessary occasionally, where the 
patient is nervous and has lost considerable sleep, to administer 
drugs which act upon the central nervous system, thereby controlling 
the pain. There are several drugs which if properly given will pro- 
2 3 



354 THE TREATMENT OF PUTRESCENT PULPS. 

duce the desired effect. The United States Pharmacopeia of 1900 
recognizes a compound powder of acetanilid which is recommended 
and can be prescribed as follows : 

1$ — Pulvis acetanilidi comp., gr. xij 

Ft. chartulcE No. 2. 
Sig. — Take one powder at once and the other in two hours, 
if not relieved. 

Another very useful prescription for acetanilid is one suggested by 
Dr. A. W. Harlan, of New York. 

1$ — Acetanilidi, gr. viij 

Syrupi simplex, f o ss 

Spiritus frumenti, q. s. ad. f§ iij — M. 

Sig. — Take one-half at once and the remainder in two 
hours, if not relieved. 

Dr. J. E. Keefe, of Chicago, suggests the following remedy by which 
he claims instantaneous and often permanent relief can be obtained: 

Ifc— Alcoholis. 

Aquas, aa f§ j — M. 

Sig. — Use as directed. 

This remedy is best administered in the form of a spray, using a watch 
case atomizer for liquids, forcing the spray well back into the nostril 
on whichever side the affected tooth is located. The application 
can be repeated as often as is necessary without any ill effects. In 
case an atomizer of any kind is not at hand, about fifteen minims of 
the remedy can be placed far back in the nostril with a suitable syringe. 

The author does not wish to be understood as suggesting these 
various internal remedies in all cases of acute abscess. No therapeu- 
tist can tell exactly what internal drugs he would suggest without 
seeing the case and knowing the history; for there are many circum- 
stances and conditions which modify the effect of drugs. Every rem- 
edy here mentioned, however, will be found useful in certain cases. 

III. Chronic Alveolar Abscess. — There are two varieties of 
chronic alveolar abscesses — those without an external opening, ex- 
cept perhaps through a cavity in the offending tooth, and those which 
are discharging through a sinus. In these cases the decomposition 
of the pulp tissue is complete; the intermediate products (ptomains 
and amido-acids) have largely been broken up, and pus has been 
formed from the tissue and fluids surrounding the ends of the roots. 

1. Abscess without Sinus. — In treating that variety of alveolar 
abscess which is without an external opening, our method of proce- 
dure is somewhat different. The tooth should be located; the rub- 



GENERAL CONSIDERATIONS. 355 

ber dam adjusted, and the teeth sterilized as before; then the pulp 
chamber is opened with a suitable round bur. Usually the pus 
flows freely, in which case it is permitted to do so, pressure being made 
on the tissue immediately over the end of the root. It should be our 
effort to mechanically evacuate as much pus at each sitting as is pos- 
sible. This being done, we have no necessity for using formaldehyd 
in the same strength solution as in those cases where the pulp chambers, 
root canals, and tubuli are filled with the intermediate and end-products. 
The modified formocresol remedy will be useful here. The canals 
should be dried with alcohol as thoroughly as possible and the remedy 
on cotton hermetically sealed in each canal. It is, however, at this 
sitting, impossible to get the canals dry, and it is unnecessary to have 
them so, for the remedy will penetrate where moisture is present. 
This is an advantage over most remedies suggested for this purpose. 
In those cases where there is a copious flow of pus at the first sitting, 
the original formula can be used, and the dressing should be changed 
every day until it can be removed without the pus flowing from the 
canals. When pus is forming rapidly at the end of the roots, the dress- 
ing soon becomes dissipated, the remedy is neutralized, and it is a 
loss of time to leave it in the canals more than twenty-four hours. 
Unless there be some complication, the pus formation should be checked 
in one or two treatments; at which time the modified formocresol 
remedy can again be used. It is now possible to change the dressing 
too often. The formation of pus has been checked, and the tooth 
should not be disturbed for at least one week or ten days, in order 
to give nature a chance to effect a cure. If at the end of this time 
there is no evidence of pus and the case gives a favorable history, the 
canals can be filled. Should there, however, be a slight odor although 
the tooth has not caused any trouble, we are not justified in filling the 
root. In these cases we can further modify our original formula by 
taking one drop of the mixture and adding two or three drops of cresol. 
It should be remembered that the value of formaldehyd in any remedy 
to be used in the treatment of these conditions depends upon the power 
this agent has of uniting chemically with hydrogen sulphid, ammonia 
and poisonous ptomains. When these substances are not present, 
formaldehyd, especially in this strength solution, is contraindicated. 
This precaution is mentioned here because formaldehyd is an irritating 
gas and any remedy containing it should be modified according to the 
conditions as found. 

Quite frequently in these alveolar abscess cases, after the formation 
of pus has been checked we have a weeping of serum from the canals. 



356 THE TREATMENT OF PUTRESCENT PULPS. 

An excellent remedy to use in this case is eucalyptol to which thymol 
has been added in the following proportion: 

1$ — Thymol, gr. x 

Eucalyptol, t"3j — M. 

Sig. — Dry the canal as much as possible and hermetically 
seal in the remedy. 

If this remedy fails to check the secretion and the fluid is serum 
not pus, no hesitancy need be felt as to filling the root, although the 
canals cannot be dried. 

Occasionally we find a chronic alveolar abscess of this variety 
where it is almost impossible to check the formation of pus by apply- 
ing drugs to the canals of the teeth. In those cases where the pus 
continues to flow freely when the dressing is removed at the third or 
fourth sitting, some complication can be expected. It is necessary 
then to force some stimulating agent through the apices of the roots, 
after the pus has been mechanically evacuated. The stimulating 
agent which the author uses almost invariably is a fifty per cent solu- 
tion of phenolsulphonic acid. This preparation is made by heating 
phenol in an evaporating dish, adding the sulphuric acid, and then 
the water, slowly, while hot. If the resulting solution is not clear, 
it should be filtered by packing cotton in the neck of a funnel and 
passing the solution through. In resorting to this means of bringing 
about a more acute condition, I desire to emphasize the necessity of 
first evacuating the pus as completely as possible before using the 
remedy, after which the agent should be gently forced through the 
apices and the modified formocresol remedy sealed in the canal. 
It will be found that one or two treatments will usually check the for- 
mation of pus, after which the case can be treated as an ordinary 
abscess of this kind. In case this method fails to effect a cure, however, 
it will be necessary to surgically establish an opening through the over- 
lying process and soft tissue and treat as for an ordinary discharging 
abscess — which treatment will now be considered. 

2. Abscess with Sinus.— -In those cases where the pus is dis- 
charging into the mouth through a sinus, our first duty is to locate the 
offending tooth. This is generally a simple matter for the reason that 
the sinus usually opens immediately over the tooth from which it 
comes. The pus in making its exit, however, follows the line of least 
resistance, and in some cases the condition of the process is such that 
the pus burrows forward or backward, and opens through the gum 
at a point several teeth removed from the one which is causing the 
trouble. These are the cases that are difficult to diagnose, especially 



GENERAL CONSIDERATIONS. 357 

where the abscess has been discharging for some time, when there is 
not much tenderness in any special tooth, and where there are several 
pulpless teeth on this side of the mouth. Sometimes two teeth con- 
taining putrescent pulps have a common sinus. In this case it would 
be impossible to heal the tract by treating only one of the teeth. The 
use of a silver probe will be valuable in all such cases. By gently 
working the probe forward or backward the sinus can be explored and 
the offending tooth or teeth located without drilling into innocent 
teeth — a discouraging procedure to both patient and dentist. The 
tooth being located, all that is necessary to effect a cure — there being 
no complication — is to force some bland solution through the root 
canal and sinus, thus being certain it is well established; cauterize 
the tract, hermetically seal in the canal or canals the same agent used 
for this latter purpose or the modified formocresol remedy, and, at 
the subsequent sitting, the case giving a favorable history, fill the root. 
Establishing Sinus. — If the abscess is not discharging, and it is 
well in those cases where it is discharging, before adjusting the rubber 
dam, to enlarge the mouth of the sinus with a lancet or bistoury. 
By dipping the lancet in phenol, this may be accomplished with very 
little pain to the patient. After this is done the rubber dam should 
be adjusted and the canals freely exposed. Now that the infection 
is past the end of the root, we need not hesitate to mechanically clean 
the canal at this sitting. The canals being clean we are ready to 
establish the sinus. To do this we need a bland solution and a good 
hypodermic syringe with a long straight needle for anterior and a long 
curved needle, for posterior teeth. There is an advantage in having 
a long needle, for the nearer the point is to the apex of the root, the 
less packing and force is required to send the solution through the sinus. 
Any bland solution can be used for this purpose. The author suggests 
peppermint water to which two minims of phenol has been added to 
the fluid ounce. A piece of unvulcanized rubber of the proper size 
should be selected, softened in the flame, and a hole made in the center 
through which the needle is placed and inserted into the canal. The 
rubber should now be tightly packed around the needle and held 
on either side with flat nose pliers, when pressure can be made on 
the piston of the syringe and the solution forced through the sinus. 
This should be repeated several times, care being taken not to break 
the needle in the canal. If convenient one corner of the dam can be 
raised, exposing the mouth of the sinus to view. There are two ob- 
jects in forcing a bland solution through the sinus: one is to be cer- 
tain that it is open, and the other is to mechanically wash out the 



358 THE TREATMENT OF PUTRESCENT PULPS. 

pus. Whenever pus can be mechanically removed, it is always better 
to dispose of it by this meansrather than to do so by the use of some 
chemical agent. It is common practice after the sinus is established 
to use a solution of hydrogen dioxid. This is often a dangerous pro- 
cedure and always unnecessary if the first solution has been used in 
sufficient quantity. For cauterizing the sinus in simple cases ninety- 
five per cent phenol has been largely employed. An excellent prep- 
aration to use for this purpose it the modified phenol solution. With 
the sinus well established, it is never necessary to place either of these 
solutions in a hypodermic syringe. The author knows of several in- 
stances where this has been tried with disastrous results. The remedy 
can be applied to the canals on cotton, when, with unvulcanized rub- 
ber and a suitable instrument, it can be forced through the sinus. 
Alcohol is a positive antidote for phenol; the alcohol bottle should 
therefore be in a convenient place so that the remedy used in the canal 
can be neutralized at once when it appears at the mouth of the sinus. 
If this has been well done, it matters little what drug or remedy is 
sealed in the canal. The modified phenol or the modified formo- 
cresol solution will give excellent results if hermetically sealed in the 
canals for about one week. In cases of long standing when we can 
reasonably suspect a roughening of the end of the root or process 
through which the pus has been discharging, it is good practice to use, 
as the cauterizing agent, a fifty per cent solution of phenolsulphonic 
acid, and in stubborn cases the pure acid can be employed. This 
agent rapidly disintegrates cotton, therefore it can be placed in the 
canal on threads of asbestos, wool fiber, or silk and forced through the 
sinus in the usual manner, cauterizing it, and also chemically dissolving 
any sharp edges of the root or process which may be a source of irri- 
tation and prevent healing. The author does not believe in delaying 
the root filling long after the sinus has been cauterized in uncompli- 
cated cases; for by filling the root as soon as'w T e are certain that the 
sinus is healing, we avoid a weeping condition, which usually exists 
and which is annoying when this part of the treatment is delayed for 
one month or six w r eeks as advocated by some writers. In these 
cases where the first treatment has been thorough, and the case gives 
a favorable history, the root should be filled at the second, or, at most, 
at the third sitting. If the case does not yield to the above treatment, 
some complication may be expected. 

It is sometimes difficult to establish the sinus, especially on molar 
teeth. In all such cases where there is no complication, the case 
can be nicelv treated with the formocresol solution as outlined under 



GENERAL CONSIDERATIONS. 359 

treatment of abscess without sinus. Before referring to complicated 
cases the treatment of putrescent pulps and abscesses associated with 
deciduous teeth will be considered. 

Treatment of Putrescent Pulps and Abscesses in Deciduous Teeth. — 
In treating the conditions under consideration, in the mouths of 
children, it is necessary in most cases to modify our usual method 
of treatment. Our first duty here is to gain the confidence of the 
child. If the abscess is associated with a deciduous molar which we 
would desire to save for at least a year or two, it can be treated nicely 
in the following manner: After gaining the confidence of the little 
patient the mouth can be rinsed with an antiseptic solution — one which 
has a pleasant taste. Then open into the pulp chamber and place 
a pledget of cotton in the opening. Now mix on one end of the ce- 
ment slab precipitated calcium phosphate and the formocresol remedy, 
making a stiff paste. On the other end of the slab have a quick set- 
ting cement ready to mix. Again rinse the patient's mouth and, keeping 
the cavity as dry as possible, gently pack the paste into the pulp 
chamber and flow the cement over it, filling the cavity. If deemed 
advisable, the cavity can be prepared in the cement and filled with 
amalgam. It is remarkable how rapidly these abscesses will heal and 
remain quiet when treated in this manner, provided, of course, there 
be no caries or necrosis of bone. 

Complications. — There are several complications of chronic al- 
veolar abscess of both varieties, with and without a sinus, where it is 
necessary to modify or change the general method of treatment to 
meet the conditions as they exist. For instance, in the case of an 
abscess without a sinus where we can reasonably suspect, and where 
the indications point to a roughening of the end of the root, we ought 
not to expect to cure the case by simply sealing remedies within the 
canals of the tooth. If we do, we are expecting too much of drugs. 
Again, in a case of an abscess with a sinus where the pus has been dis- 
charging for several months, with the not unusual result that the end 
of the root or process through which the pus has discharged has 
become roughened, we should not expect to effect a cure by forcing 
phenol or modified phenol through the sinus; because such agents as 
these have no action whatever on the bony structures. 

' i. Denuded End of Root. — One complication we may expect to 
find in abscesses of long standing, especially in the variety without 
a sinus, is where a large area of tissue in the apical space has been ab- 
sorbed or broken down, denuding the end of the root and the denuded 
portion projecting into the absorbed area. It is possible, in these 



360 THE TREATMENT OF PUTRESCENT PULPS. 

cases, to make pressure over the end of the root and mechanically 
evacuate all of the pus above the apices; but we cannot expect by 
this means to evacuate the pus below and surrounding the end of the 
root projecting into the space. In this case we must do one of two 
things: Force some stimulating agent through the end of the root 
into the infected area, to create a more acute condition, or surgically 
establish a sinus through the overlying process and soft tissue and 
treat as an ordinary discharging abscess. While the author does not 
hesitate to adopt the latter method if necessary to effect a cure, it 
will be found that the use of a stimulating agent will generally suffice 
in these cases. The agents recommended are a- fifty per cent solution 
of phenolsulphonic acid, or a fifteen per cent solution of trichloracetic 
acid. In using either of these solutions the pus should first be evac- 
uated as much as is possible; then the solution selected can be placed 
in the canal and gently forced through the apices and the modified 
formocresol solution sealed in the canal. One or two treatments will 
usually be sufficient to check the pus formation, when the case can be 
treated in the ordinary manner. 

2. Absorbed Root. — Another complication of both varieties of 
chronic alveolar abscess is where the pus has stood in contact with 
the end of the root sufficiently long to cause an absorption, leaving 
a roughened end which irritates the tissue and prevents healing. 
Sometimes, also, the process through which the pus has burrowed is 
left with sharp edges. In all such complications the "acid treatment" 
is especially indicated. These cases generally yield nicely to the treat- 
ment if phenolsulphonic acid is used as the agent with which to cau- 
terize the sinus, as the acid dissolves any sharp edge of root or process. 

3. Encystment oj Root. — A difficult complication to treat is where 
an abscess occurs on a root, the end of which has become encysted 
from deposits, excementosis or other causes. In order to effect a cure 
in these cases, it is necessary to establish a sinus and remove the de- 
posits, excise the root, or extract the tooth. The method of excising 
the root will be discussed later. 

4. Involving Vault. — Still another complication often difficult to 
cure is where the pus has worked its way through the lingual plate of 
bone and involves the vault of the mouth. The dense fibrous tissue 
covering the vault is very tough and the pus often separates the perios- 
teum from a considerable area of bone before ultimately discharging 
into the mouth. Generally a lancet is required to evacuate the pus. 
In treating these conditions it is essential to explore the affected area, 
using a sharp steel instrument in order to determine whether there is 



GENERAL CONSIDERATIONS. 36 1 

caries or necrosis. Unless too much bone is involved the case can be 
successfully treated by first making a liberal opening with a sharp 
bistoury and, if necessary, breaking down the sharp edges of bone ; 
through which the pus has burrowed, with a round bur having a long 
shank, after which the sinus should be established in the usual manner, 
using a considerable quantity of the bland solution. Now dry the 
canal and force through the sinus full strength phenolsulphonic acid. 
Sometimes it is advisable to place a piece of blotting paper soaked in 
liquid vaselin over the lingual opening when forcing the acid through. 
This causes the agent to spread and come in contact with the entire 
area involved. Alcohol and the oils will neutralize any excess of the 
phenolsulphonic acid that may get on the other tissues of the mouth. 
This treatment should be repeated as often as the case demands. 
When there is no evidence of pus and the case has healed sufficiently so 
that there is only a watery discharge the root can be filled. 

5. Secondary Abscess Pocket. — Occasionally we find an abscess 
of the discharging variety which does not yield to our general treat- 
ment, yet we are reasonably certain that none of the complications 
so far mentioned are present. In these cases we can suspect a secon- 
dary abscess pocket. This is especially true where the sinus opened 
into the mouth several teeth removed from the affected tooth. This 
pocket can usually be discovered by the aid of a small silver probe 
The treatment is simple — all that is necessary is to open the pocket, 
wash it out first with a bland solution, then inject fifty per cent phenol- 
sulphonic acid. In using phenolsulphonic acid in such cases it cannot 
be injected through the tooth, therefore it is necessary to use a syringe 
— a glass syringe with an asbestos-packed plunger and a gold or a plat- 
inum needle should be used. 

(6.) Involving Antrum. — The pus in making its exit follows the 
line of least resistance, and sometimes it is easier to work its way 
through the floor of the antrum than through the labial or lingual 
plate of bone. The treatment of this complication will not be dis- 
cussed here; but in this connection it is well to remember that so good 
an authority as Kyle, viewing the question from the nasal side, finds 
that fully fifty per cent of antral diseases are of dental origin. 

Excision of Root. — In all complicated abscesses which will not 
yield to the treatment outlined above, we can often save the root by 
excising its end. This should be done only as a last resort and then 
under the most aseptic measures. The hands of the operator, as well 
as all instruments used, should be thoroughly sterilized. Before 
operating, the root should be filled and a thorough exploration made 



362 THE TREATMENT OF PUTRESCENT PULPS. 

that the amount of process and root involved may be noted. A local 
anesthetic injected deeply should be employed and a circular incision 
made. The opening can now be packed with gauze dipped in a 1.1000 
solution of adrenalin chlorid for a few minutes. In all large roots 
the author prefers following the method of Dr. Thos. L. Gilmer, of 
Chicago. With a spear-shaped drill a hole can be made through the 
center of the root after which the root is easily excised with a fissure 
bur, placing the bur in the hole and drilling mesially and distally. It 
is often difficult to remove the end after the excision is made. This 
can be done with a strong hatchet or hoe excavator, an elevator and 
sometimes with small beaked root-forceps. After removing the excised 
end, the root remaining should be smoothed with a round bur and the 
area thoroughly curetted, removing any necrosed process which may 
be present. The wound should now be washed with an antiseptic 
solution and packed with sterile gauze. The patient should be in- 
structed to keep the mouth as clean as possible and the packing should 
be changed every two days until granulation begins to fill the space. 

Whenever the operator is in doubt as to the best means of treating 
complicated alveolar abscesses, he should never hesitate to consult 
with a practitioner who has had more experience in treating these 
cases. Such a course cannot be construed as a lack of knowledge, 
but is evidence of conservatism and progress. 

Pericemental Abscess. — All of the alveolar abscesses which we have 
discussed thus far in this chapter have been the result of an infection 
in the apical area, the infection being due to pathogenic bacteria, 
poisonous ptomains and irritating gases, which have escaped from a 
putrescent root canal. There is, however, an abscess that occurs in 
the alveolar region about the roots of teeth, not caused from the source 
mentioned. This particular kind of abscess occurs in connection 
with live teeth; not necessarily so, however. There is a progressive 
breaking down of the pericemental membrane and in dental literature 
it is called a pericemental abscess. The cause of this particular 
kind of abscess is rather vague; but it is generally supposed to be due 
to some traumatic injury. It frequently occurs on the labial surface 
of the roots of the anterior teeth involving most of this surface. They 
have also been known to occur between the roots of molar teeth, es- 
pecially the upper molars. While a pericemental abscess is often 
associated with pyorrhea alveolaris, care should be exercised, in mak- 
ing the diagnosis, not to get this condition confused with the latter 
disease. 

Treatment. — For convenience in outlining our treatment for a 



GENERAL CONSIDERATIONS. 363 

pericemental abscess, the condition may be classified as acute and 
chronic. As a rule there is very little pain associated with either 
variety of pericemental abscess. In the acute form, which, as such, 
is extremely difficult to diagnose, the patient will complain of " some- 
thing being wrong with a particular tooth." About all that can be 
done therapeutically with the acute form is to pacify the patient 
as best we can until the acute abscess develops into the chronic variety, 
when pus is formed and discharges usually at the gum margin, and 
thus the diagnosis is more easily made. If the abscess occurs on the 
anterior teeth where the area involved can be curetted and cauterized 
it will generally yield to the treatment; but the treatment of a chronic 
pericemental abscess on molar teeth is at best a discouraging procedure 
and practically the only permanent cure is to extract the affected tooth. 
In those cases where the area can be reached, an opening, if necessary, 
can be made through the gum, the root thoroughly scraped and pol- 
ished, then after washing out the abscessed area, it should be cauterized 
with some cauterizing agent. Nothing gives better results than phenol- 
sulphonic acid. With a proper glass syringe and a gold or platinum 
needle, the remedy can be injected into the abscess pocket. One 
thorough treatment should effect a cure. In curetting these cases it is 
far better to go a little beyond the affected territory rather than fail 
to remove all of the affected tissue and have the abscess recur. Where 
the abscess can be reached, thorough curettment and cauterization 
will effect a cure. That portion of the pericemental membrane which 
has been destroyed will perhaps never be regenerated, but if we succeed 
in having granulation fill in the area involved, even though the mem- 
brane is not regenerated over that particular surface of the root, the 
tooth can be saved for a considerable length of time. 

Filling Root Canals. — There are so many different methods of 
filling root canals, and there seems to be such a variance of opinion 
as to the best method of performing this operation, that it is with a 
degree of hesitancy that the author attempts to discuss this subject. 
This operation stands as a sort of dividing line between the subjects 
of therapeutics and operative dentistry proper. In discussing this 
subject the author will present the therapeutic aspect and describe 
a method of procedure which has proved successful in his practice. 

It will be remembered that three factors were emphasized in the 
chapter on pulp removal and the subsequent treatment, viz.: 

1. Established and maintained asepsis. 

2. Preserve the color of the tooth. 

3. Thoroughly fill the canal. 



364 THE TREATMENT OF PUTRESCENT PULPS. 

The author suggests tilling all canals, which are large enough for a 
broach to enter, with gutta-percha in the manner which will be sub- 
sequently described. In connection with the preservation of the color 
of the tooth, it should be mentioned that white base plate gutta-percha 
should be used, especially for the purpose of dissolving in chloroform, 
making chloro-percha. If this white substance is forced into the 
tubuli of the crown of the tooth, as it is liable to be, it will not change 
the color of the tooth structure as would the pink gutta-percha. A 
great many dentists have been moistening the canal, previous to filling 
with gutta-percha, with oil 0] eucalyptus; and, as a result, much unneces- 
sary pericementitis has followed this operation. If oil of eucalyptus is 
used at all, the refined oil only should be selected; and, far more satis- 
factory results will follow the use of eucalyptol, the most volatile con- 
stituent of oil of eucalyptus. While eucalyptol is irritating, it is not 
nearly as much so as is oil of eucalyptus. The author suggests modify- 
ing the irritating property of eucalyptol and enhancing its antiseptic 
power by combining menthol and thymol as suggested in the prescrip- 
tion for modified eucalyptol in the chapter on The Treatment of 
Ordinary Pericementitis. 

In this proportion the agents added do not interfere with the solvent 
power of eucalyptol for gutta-percha; but if the amounts are increased 
to any appreciable extent this does not hold true. 

In filling root canals it is always the safest practice to adjust the 
rubber dam, for asepsis must be established and maintained. The 
same agents can be used for sterilizing the teeth after the dam is ad- 
justed as were described in removing pulps by the anesthetization 
method. The canals should be aseptic before the operation is at- 
tempted. If there is any doubt in this regard the operation should be 
deferred until the canals are in such a condition. 

Filling Large Canals. — In rilling large canals, especially those 
in connection with which abscesses have been treated, where the apex 
is large and where we ought not to expect to get a response from the 
patient when the gutta-percha cone reaches the apex, on account of 
the absorption in the apical area, it is best to measure the canal and 
then use one cone which approximately fits the canal rather than use 
two or three smaller cones with the possibility of forcing one through 
the apex and into the apical area. There is almost as much danger 
of forcing the root filling too far in large canals, as there is in not forcing 
it far enough in small canals. To measure the canal, cotton can be 
tightly wrapped around a smooth, sterile broach and inserted. When, 
by repeated trials the cotton fits the canal, a cone can be made of white 



GENERAL CONSIDERATIONS. 365 

base plate gutta-percha, which is slightly smaller than the tightly 
wrapped cotton. The canal should now be moistened with modified 
eucalyptol, flooded with white chloro-percha, working the latter up or 
down into the canals with a fine smooth broach, exhausting the air. 
If cotton is wrapped around the broach used for this latter purpose, 
only a few shreds should be used; for we should avoid making a piston 
out of the broach and thus defeating the means of exhausting the air. 
This accomplished, the cone can be slowly and gently pressed to place. 
In filling large canals from which live pulps have recently been re- 
moved, the patient will generally flinch before the cone reaches the 
apex. When this occurs, we should wait a few moments, when the cone 
can be gently pressed much farther without causing the patient to 
flinch a second time. If these precautions are observed, they will be 
the means of preventing much of the pericementitis following the 
filling of root canals. 

Small Canals. — In filling all canals w r here we can enter nicely 
with a smooth broach, it is best to follow the technique outlined above, 
using a cone which will enter the canal. However much we may re- 
gret it, there are canals, especially in the molar teeth, so small and 
tortuous that even a fine, smooth broach will not enter; at least to any 
depth. It is useless to try to fill such canals with a gutta-percha cone. 
The methods of enlarging the canals by the use of acids and caustics, 
as referred to in connection with the destruction of pulp tissue in such 
canals, can be employed; but it is not always advisable to enlarge 
them sufficiently to admit a small cone. After the larger canal or 
canals in a multirooted tooth are filled in the ordinary manner, the 
smaller ones can be moistened with modified eucalyptol and chloro- 
percha worked up or down into the canal. This process should be 
kept up for some time and until the chloroform has nearly evaporated, 
leaving the gutta-percha quite plastic. The sides of the pulp chambers 
can now be moistened with modified eucalyptol and a piece of base 
plate gutta-percha, selected and softened in the flame, can be packed 
into the pulp chamber, when pressure can be made towards the small 
canals and the plastic gutta-percha forced into them. This is much 
better practice than simply filling the mouth of the canal with a gutta- 
percha cone. If the canal is so small and tortuous that even a small 
broach will not enter, and if it cannot be enlarged by the use of acids 
or caustics, as referred to in a previous chapter, it is good practice to 
make a paste of formocresol and precipitated calcium phosphate, 
placing the paste over the mouth of the canal and covering it with 
cement. 



366 THE TREATMENT OF PUTRESCENT PULPS. 

A.S previously mentioned there are many methods of filling root 
canals by which good results are attained. The method here outlined 
has served the author well. In closing this chapter I desire to say 
that no reasonable amount of time should be considered lost in treat- 
ing the conditions discussed in this chapter and in properly preparing 
canals for the insertion of the filling material. 



CHAPTER XXIII. 

THE CAUSES AND TREATMENT OF DISCOLOR- 
ATIONS OF TEETH. 

BY J. P. BUCKLEY, PH. G., D. D. S. 

General Consideration. — In the discussion of the methods of 
removing pulps from teeth and the subsequent treatment, the treating 
of putrescent pulps and the various kinds of alveolar' abscesses, the 
author endeavored to emphasize the necessity of preserving or restoring 
the color of the tooth. There is, perhaps, nothing more annoying to a 
conscientious dentist and to an appreciative patient than a discolored 
tooth in the patient's mouth. If the precautions, which have been 
mentioned in the preceding chapters, with reference to this factor 
are observed in the treatment of teeth, the necessity for bleaching 
may often be avoided; for after all that has been written on this subject 
is studied, it must be admitted that the most successful method of 
bleaching teeth is to so treat them that they will not need to be bleached. 
There are three principal sources of the discoloration of tooth struc- 
ture, viz., pulp decomposition, remedial agents and metallic fillings. 
The greatest source is that of pulp decomposition. Many teeth con- 
taining putrescent pulps are discolored before the patient presents 
for treatment. In those cases where the color is not lost the putrescent 
condition can be corrected and the color preserved by the method of 
treatment outlined in a previous chapter. 

There are two ways by which the discoloration is produced, i. e., 
by solutions which stain the cement-like substance uniting the tubuli, 
and by the ingress into the tubuli of insoluble coloring substances. 
For instance, many remedial agents in solution such as oil of cassia, 
silver nitrate, etc., have the property of staining the cementing sub- 
stance and producing discolorations; while the sulphids formed from 
certain metals, as for example in amalgam fillings, produce discolor- 
ation by virtue of being forced into the tubular structure of the dentin. 
If more care were taken in selecting remedial agents, used in the 
treatment of teeth, which would not stain the tooth structure, and if 
high grade alloys were selected in making amalgam fillings, the cavity 

367 



368 CAUSES AND TREATMENT OF DISCOLORATIONS OF TEETH. 

properly prepared, amalgam inserted and polished when set, there 
would be few teeth discolored from these sources. 

Occasionally, however, teeth have been observed to assume a 
pinkish hue shortly after some traumatic injury, rapid regulation 
or after the application of some irritating drug had been applied 
to some small exposure of the pulp as, for instance, arsenic trioxid. 
It was stated in a previous chapter, that it is always best to apply 
arsenic trioxid to the dentin immediately over the pulp, even though 
an exposure exists. Dr. E. C. Kirk, of Philadelphia, has offered a 
plausible explanation for the cause of this immediate discoloration. 
He says, " It is now known that the pink staining of the tooth is brought 
about by a rupture of the stroma of the red blood disks liberating their 
contained hemoglobin, which dissolves in the plasma, forming a 
solution of hemoglobin which readily penetrates the dentinal tubuli, 
the lumen of which is of insufficient diameter to admit the unbroken 
red corpuscle. This pink discoloration resulting from the infiltration 
of hemoglobin solution represents the first stage of tooth discoloration. 
The pink stain readily undergoes alterations, later on assuming a 
brownish tint, due to the breaking down of the highly complex mole- 
cule of hemoglobin into a reduction product known as hematin." 
But as has been stated, many teeth containing putrescent pulps are 
discolored before the patient presents for treatment, and inasmuch 
as this is by far the greatest source it is well to try to ascertain definitely 
the true cause of the discolorations from this source; for, it is difficult 
and unsatisfactory to try to bleach a tooth when we have no knowledge 
of the nature of the pigment we are trying to bleach. 

The principle which governs the successful bleaching of teeth 
is to chemically change the molecule of the pigment in such a manner 
as to destroy its color, or chemically change the insoluble coloring 
substance to a soluble form, when it can be washed out of the tooth 
structure. Attention will now be directed to the cause of discoloration 
from pulp decomposition as the author understands it. In the chapter 
on the Chemistry of Pulp Decomposition, the intermediate and 
end-products resulting from this complicated process were enumerated 
and it was ascertained that ammonia, NH 3 , and hydrogen sulphid, 
H 2 S, were the principal gases formed. It was also pointed out that 
the relative amount of nitrogen and sulphur found in the proteid 
molecule was fifteen per cent of the former to 0.3 per cent of the 
latter; and from this fact it was reasoned that ammonia, a compound 
of nitrogen and hydrogen, was generated in far greater quantities in a 
putrescent root canal, than hydrogen sulphid, a compound of hydrogen 



GENERAL CONSIDERATIONS. 369 

and sulphur; and that this latter gas did not assume the important 
role in the discoloration of teeth from this source, as had been so 
generally supposed. 

It is quite generally conceded by those who have given this phase 
of the decomposition process their attention, that iron, Fe, is the 
most important element to be considered in the many factors entering 
into the discoloration problem; and it is a common statement found 
in our text-books and journals that the discoloration is due to the 
formation of ferrous sulphid, FeS, which salt is supposed to be 
formed by the action of hydrogen sulphid upon the iron. This view 
is held by many writers, among whom is Dr. Kirk, who has perhaps 
given more thought to this subject than any other writer. The source 
of iron has been considered entirely from the decomposition of the 
hemoglobin of the red blood corpuscles; for it is well known that this 
compound contains iron, which is not characteristic of all proteid 
bodies. Dr. J. E. Hinkins, of Chicago, in his analysis of the enamel 
and dentin of human teeth, found that iron existed in both of these 
structures in combination with aluminum. It is not unlikely that 
future investigation will find that the iron from this source plays a 
part in the discoloration of tooth structure. It remains, however, 
to be demonstrated that ferrous sulphid is the true cause of the dis- 
coloration and the author doubts if this theory can ever be proved 
to be correct. From chemistry we learn that ferrous sulphid is a 
black compound and that no change takes place in the color or other- 
wise by exposing it to the air. Should the discoloration of tooth 
structure be due, then, to ferrous sulphid, as claimed by many writers, 
there would be no necessity, in treating putrescent pulps, so far as 
preserving the color of the tooth is concerned, for using a remedy 
which can be hermetically sealed within the tooth. Clinical ex- 
perience shows that a tooth containing a recently decomposed pulp, 
in a large percentage of cases, is not discolored, and that such a tooth 
will not change in color if the formocresol remedy is used in the 
treatment and always hermetically sealed. 

Dr. Kirk admits that, "Ferrous sulphid, as such, cannot be held 
wholly accountable for the bluish-black color of the tooth which has 
reached the stage of permanent discoloration." Neither can the green 
nor yellow discolorations of teeth be attributed in any way to the presence 
of black ferrous sulphid; yet, the author is of the opinion that it is 
possible for this compound to be formed in the ultimate process of 
pulp decomposition as will be explained later on in this chapter. 
From the foregoing, it must be evident that it is necessary to search 
24 



for other colored substances, besides black ferrous sulphid, which 
are possible to be formed in the process of pulp decomposition and 
which are capable of staining the tooth structure. 

In articles which the author read before the Odontographic Society 
of Chicago {Dental Review , June, 1901, October, 1902), a theory 
was advanced which explained the variety of colors exhibited in dis- 
colored teeth, and while some criticism has been offered in regard to 
this theory, he is still of the opinion, that it presents today the most 
rational solution of this question from both the chemical and clinical 
viewpoint. 

As has been stated, ammonia is not only a constant end-product, 
but it is generated in far greater quantities than any other gas. It is 
well known that ammonia has the property of uniting chemically 
with water, which is always present in a putrescent root canal, form- 
ing ammonium hydroxid, NH 3 + H 2 = NH 4 OH. This reagent 
will act upon the soluble salts of iron, in both the ferrous and ferric 
forms, producing respectively, ferrous and ferric hydroxid, Fe(OH) 2 , 
Fe 2 (OH) 6 . Therefore, it is not only possible, but quite probable, 
that the atomic iron which is liberated in the process of decomposition, 
from the hemoglobin or perhaps intermediate compounds containing 
it, unite with the ammonium hydroxid present, forming the hydroxid 
of the metal; and inasmuch as the compounds containing the iron 
are organic or weak, the ferrous hydroxid, in all probability, would be 
produced. Ferrous hydroxid is a white compound which readily 
absorbs oxygen when in the moist state and exposed to air, and grad- 
ually changes to ferric hydroxid, a reddish-brown compound. In 
this change there is an array of four distinct colors — white, green, 
black and brown — and in the blending of these four colors there is 
produced every variety of shades exhibited in discolored teeth. This 
seems to suggest a plausible explanation as to why teeth containing 
putrescent pulps change color when air is admitted; also why a tooth 
containing a recently decomposed pulp is not discolored and does 
not readily change color until air is admitted. I fully recognize the 
fact that ferrous hydroxid is not the only compound of iron capable 
of producing color changes when moist and exposed to air. Nearly 
all of the ferrous compounds change more or less; but with the possible 
exception of ferrous carbonate, which could be formed, ferrous hy- 
droxid is the only compound of iron possible to be produced, the color 
changes of which correspond to those seen in teeth which have reached 
the stage of permanent discoloration. 

I have stated in this chapter that, in my opinion, it was also possible 



GENERAL CONSIDERATIONS. 371 

for ferrous sulphid to be formed ultimately by the putrefactive process; 
but it can only be produced by the hydrogen sulphid acting first upon 
the ammonia, forming ammonium sulphid, H 2 S + 2NH3 = (NH 4 ) 2 S. 
This alkaline reagent will act upon the soluble salts of iron, precipi- 
tating the metal as ferrous sulphid. My conclusions, then, with 
reference to the true cause of the discoloration, are these: that the 
permanent yellow discoloration is due to the formation of ferric 
hydroxid ; the bluish-black discoloration to a mixture of ferric, hydroxid 
and ferrous sulphid — or to a failure of the ferrous hydroxid to become 
completely oxidized into the ferric form owing to a lack of moisture 
or oxygen; the other colors observed are transitory and are due to the 
gradual transition of the ferrous into the ferric hydroxid. In coming 
to these conclusions I have accepted the statement that iron plays 
the most important role of all the elements entering into the discolor- 
ation problem; for if it were possible to remove the hemoglobin from 
the blood or the iron from the hemoglobin, I do not believe the dentin 
could be discolored by any compound possible to be formed by the 
process of pulp decomposition. If this be true, my reasoning is at 
least logical. 

Having thus far, in this chapter, discussed the cause of the dis- 
coloration of tooth structure, the methods of restoring the normal 
color will now be considered. 

When a case presents for bleaching there are three important 
things to be determined: 

(1) Ascertain, if possible, the cause of the discoloration. 

(2) Decide whether or not the color can be successfully restored. 

(3) The selection of the proper bleaching agent with which to 
restore the color. 

The general cause of the discoloration can usually be ascertained 
from the history of the case as related by the patient. Whether or 
not the tooth can be successfully bleached depends largely upon the 
cause of the discoloration, the condition of the tooth structure, and 
the length of time the tooth has been discolored. Experience will 
prove that the teeth which will permanently retain their color, after 
it is restored, are those that have a good bulk of dentin and which 
dentin can be protected by the remaining enamel and some filling 
material, preferably porcelain if this material is at all indicated. I 
desire to emphasize the fact that it is folly to expect a tooth to retain 
its color any length of time after once being bleached unless the dentin 
is properly protected. 

Having ascertained the cause of the discoloration and believing 



;;2 CAUSES AND TREATMENT OF DISCOLORATIONS OF TEETH. 

that the condition of the tooth structure justifies us in attempting to 
bleach the tooth, we come to the most important consideration, viz., 
the selection of the bleaching agent, with which the color can be 
restored with the least inconvenience to the patient and operator. 

Methods. — All of the methods employed in bleaching teeth involve 
more or less chemistry; and from a chemical viewpoint there are two 
general methods of bleaching teeth — oxidation and reduction. 

I. Oxidation Method. — This general method is of two kinds also 
direct and indirect. 

(i) Direct. — By direct oxidation is meant the use of any agent or agents 
from which oxygen can be directly obtained. The agents used for 
the purpose are: 

Sodium dioxid, Na 2 2 . Twenty-five per cent ethereal solution of 
hydrogen dioxid. H 2 2 . Alphozone, (COOH. CH 2 . CH 2 CO) 2 - 
2 . Aluminum Chlorid, A1 2 C1 6 , and a three per cent aqueous 
solution of hydrogen dioxid. Oxalic acid, H 2 C 2 4 . 2H 2 0. 

(2) Indirect. — By indirect oxidation is meant the use of any agent or 
agents by which oxygen can be obtained indirectly. The agents 
employed are such as will liberate nascent chlorin, CI, a chemic- 
ally active gas, which, in the presence of moisture seizes upon a 
molecule of water, H 2 0, abstracts the atoms of hydrogen, H, 
forming hydrochloric acid, HO, and liberates the oxygen, O, in the 
nascent state, as H 2 + 2C1= 2HCI- + O (nascent). Some of 
the agents used for this purpose are: 

Aluminum chlorid and a freshly prepared Labarraque's solution 

(Harlan). 

Chlorinated lime and dilute acetic acid (Truman). 

Powdered alum, A1 2 K 2 (S0 4 ) 4 , and Labarraque's solution. 

Solution of sodium chlorid electrically decomposed. 

II. Reduction. — By reduction is meant the use of any agent or 
agents which will abstract oxygen from a compound containing it. 
The agents which have been recommended are, sodium sulphite, 
Xa 2 S0 3 , 10 parts, and boric acid, H 3 B0 3 , 7 parts. These are 
mixed and placed within the tooth, moistened with water and her- 
metically sealed. (Kirk.) A reaction occurs between the two sub- 
stances with the ultimate formation of sulphurous acid which has a 
great affinity for oxygen and is therefore a good reducing agent. In 
some cases where the tooth has been discolored by remedial agents 
and where it is desired to break up the color molecule, good results 
are obtained bv this method. Whenever the method is used the 



GENERAL CONSIDERATIONS. 373 

tooth should subsequently be thoroughly washed with an alkaline 
solution such as a ten per cent solution of sodium bicarbonate or 
borax to neutralize the acid. 

In most cases of discoloration the direct oxidation method is 
preferable and in view of the fact that all of the agents used in the 
direct method of bleaching depend upon the generation of oxygen 
for their efficacy, it can readily be understood that the direct method 
is far more satisfactory. The fact, also, that hydrochloric acid is a 
constant by-product in the indirect method, thereby creating an acid 
medium, adds to the objectionable features of this method; for manu- 
facturers have recognized for years that better results can be obtained 
in bleaching ivory, wool, hair, feathers, etc., when the bleaching process 
was carried on in an alkaline medium. This is likewise true in bleach- 
ing teeth. Believing then, that the direct oxidation method is far 
superior to the indirect, I shall not burden my readers by describing 
the latter method; but will direct attention to the detailed use of sodium 
dioxid — a direct oxidizing agent and one which, if its chemical prop- 
erties are known and its dental application understood, the author 
believes to be the best agent for bleaching teeth thus far suggested to 
the profession. 

Sodium dioxid was introduced by Dr. Kirk in 1893. It is a rare 
chemical, not because it is difficult to manufacture, but because of 
the fact that in the past there has been little demand for it. Its 
chemical activity precludes its use on soft tissue; hence, it is scarcely 
known to the medical profession, and is not kept in many pharmacies. 
It is the oxid formed when sodium is allowed to burn briskly in dry 
air or oxygen. The product occurs in commerce as a yellow powder 
and is readily decomposed by water into caustic soda and oxygen. 
Because of this latter fact, much of the product obtained from whole- 
sale druggists, labeled "sodium dioxid," is nothing but caustic soda. 
This accounts for the fact that many dentists have tried this method 
of bleaching and failed to get results. The fault is not with the method, 
but with the powder used. In order that we might be able to ascertain 
the efficacy of the chemical, some years ago I devised a simple chemical 
test for this purpose. In a clean, dry test tube place about one gm. 
(15 grs.) of the powder and to it add 1 or 2 c. c. (15 or 30 m.) of water. 
If the specimen is good sodium dioxid, enough oxygen should be 
generated to kindle a glowing splinter held at the mouth of the tube. 
Having tested the chemical and proved it to be sodium dioxid, and not 
caustic soda, the next thing is to properly prepare the tooth, which, 
of course, should have been previously treated and the root filled with 



374 CAUSES AND TREATMENT OF DISCOLORATIONS OF TEETH. 

gutta-percha. The rubber dam should be adjusted, if possible without 
the use of the steel clamp. The ligature should be wrapped twice 
around each tooth included in the dam, which should be at least two 
teeth on either side of the one to be bleached. This will prevent the 
by-product, caustic soda, from getting on the soft tissue and destroying 
it. The lower third of the root filling should now be removed with a 
good sized round bur— it being necessary, for permanent results, to 
bleach the tooth rootwise as far as possible. We are now ready to 
apply our bleaching agent. Both the dry sodium dioxid and a solution 
made by carefully dusting the powder into ice water is recommended 
to be used. The best results are obtained by using the dry powder, 
placing it into the cavity and with a platinum broach or pointed glass 
instrument, work the powder well up into the canal from which the 
root filling has been removed. Care should be taken not to use steel 
instruments, as the oxygen will attack the steel forming ferric oxid 
and therefore we may get into the tooth the pigment we are trying to 
remove. In some cases it is rather difficult to place the powder in the 
cavity without getting it on the patient's face or clothing. To over- 
come this a strip of unannealed i.iooo platinum foil can be placed 
between the discolored and adjacent tooth, letting it extend above 
or below the cutting edge, as the case may be, when white base plate 
gutta-percha can be warmed and pressed against the lingual surfaces 
of the teeth included in the dam. This forms a pocket on the labial 
side into which the powder can be easily placed, using a little gold or 
platinum spoon or spatula. In more difficult cases a paste can be 
made of the powder and chloroform, in which it is insoluble, quickly 
packing the paste into the cavity, evaporating the chloroform, leaving 
the dry powder where it is desired. Distilled water is now dropped 
upon the powder, causing a lively effervescence and the following 
reaction takes place: Na 2 2 + H2O = 2NaOH + O (nascent). 
This nascent oxygen is a powerful oxidizing agent. It attacks and 
rapidly destroys any organic matter which may be present in the 
tubular structure of the dentin. It also thoroughly bleaches vegetable 
colors and acts upon any iron compounds which may have produced 
the discoloration. It converts ferric hydroxid, if present, into ferric 
oxid — still an insoluble compound. If ferrous sulphid is present in 
the moist state, it may be converted into ferrous sulphate, a soluble 
salt; but in the presence of caustic soda it would be reprecipitated as 
ferrous hydroxid, which, in turn, in the presence of oxygen, is at once 
reconverted into ferric oxid. Therefore, the pigment to be removed, 
if our chemical reasoning is correct as to the cause of the discoloration 



GENERAL CONSIDERATIONS. 375 

from pulp decomposition, is ferric oxid, an insoluble compound and 
must be removed mechanically by washing the tooth. Its removal is 
facilitated by the by-product, caustic soda, acting upon any fatty 
substances — fat being an end-product of the putrefaction of the proteid 
material — which may be present in the tubuli. The result of this 
action being a soluble soap, the removal of which by washing, aids, 
as stated, the mechanical removal of the insoluble pigment. 

It is my opinion that the ultimate success depends quite as much 
upon the mechanical removal of the coloring matter as upon the 
chemical destruction of it; therefore, the necessity for thoroughly 
washing the tooth after each application of the bleaching agent. 
Warm distilled water should be used in a strong syringe, letting a 
moist sponge absorb the water. The cavity is now dried, the color 
of the tooth observed and the process repeated, if necessary. Usually 
two or three applications are sufficient. If the color is not readily 
restored, the dentin can be saturated with a two per cent solution 
of sulphuric acid which can now enter the tubuli and chemically 
convert the oxids, that may not have been mechanically or other- 
wise removed by the saponifying and washing process, into sulphates. 
The salts produced are freely soluble and can readily be washed out 
by again using the warm water. When the tooth is satisfactorily 
bleached, a paste of precipitated calcium phosphate and distilled 
water can be placed in the cavity, packed into the lower third of the 
root and burnished, with a warm burnisher, against all exposed dentin. 
This is thoroughly dried by burnishing, the excess removed, and a 
light-colored, quick-setting cement used to form a base for the final 
filling which had better be inserted before the dam is removed. 

In conclusion I desire to say that in the bleaching of teeth we 
find a practical application of the science of chemistry to the practice 
of dentistry; and that in the discoloration of tooth structure from the 
various sources can be found a fruitful field for further investigation. 



CHAPTER XXIV. 
THE TREATMENT OF CHILDREN'S TEETH. 

BY C. N. JOHNSON, M. A., L. D. S., D. D. S. 

This subject naturally divides itself into two parts — the man- 
agement of the child, and the management of the teeth. Tempera- 
mentally, physically and nervously there is so much difference in 
children that to ignore this factor and prescribe a set method of practice 
for all cases would result in confusion, failure and disaster. 

The first visit of a child to the dentist is usually a momentous 
occasion. Sometimes it is undertaken with the direst dread, at 
others with the most eager anticipations; all dependent on the point 
of view given the child by the parent. The dentist's duty is to study 
the temperament of the child most carefully, and he should not con- 
tent himself with anything short of obtaining a perfect mastery over 
the child, at least during the time the latter is in his office. The 
means to be employed in gaining this mastery are as varied as are the 
manifestations of juvenile human nature — probably the most varied 
of anything in psychological study. 

The chief factor, the fundamental basis of success in controlling 
children, is the exhibition of extreme kindness and the cultivation 
of infinite patience. Unless a dentist can bring this kind of an attitude 
to the management of his young patients he would better not attempt 
their treatment. And yet there are some children so unruly by 
nature and so spoiled by false training at home that to obtain com- 
mand over them in the dental chair the operator must be firm with 
them almost to sternness. If the parent has no control over the 
child, as is sometimes unfortunately the case, then the dentist should 
be the means of giving the child what is probably its first real lesson 
in discipline. And let it be said that no class of men, not even medical 
practitioners, are placed in so favorable a relationship to these young 
patients for the purpose of instilling into them obedience and stability 
of character as is the dentist, and if the members of our profession 
would only rise to the possibilities of their opportunities in this regard 
they would do no small part in developing true manhood and woman- 
hood in the rising generation. To bring up a child with no idea of 

377 



378 THE TREATMENT OF CHILDREN'S TEETH. 

individual responsibility, to foster a tendency toward avoiding any 
duty of a disagreeable nature, to always sprinkle roses for the child 
to tread upon, is weakening in its effect and results in deterioration 
of character and the pitiable failure to meet the emergencies of life 
as they inevitably arise. 

A discriminating dentist can do much in his professional relation- 
ship with these young minds to develop in them stamina and force 
of character, and it is sometimes the case that the first real experience 
of facing and properly meeting an issue is fought out in the dental 
chair. To be successful in the management of children under these 
trying circumstances a dentist must be a rare student of human nature, 
and he should early learn just when to be yielding and tender, and 
when to be firm as adamant. But let it always be remembered that 
under no circumstances, however trying the case may be, should he 
allow himself to lose his own self-control and display temper or im- 
patience; and whenever it has been necessary to be firm and even 
severe, he should invariably soften his demeanor by the utmost kind- 
liness and an unmistakable interest in the little patient's welfare. 
To gain complete control of a child who previously has never been 
controlled by any one is no mean achievement, and the sense of 
satisfaction in the good attained is well worth all the effort it requires 
to accomplish it. 

One feature of the management of children in the dental office 
which in this enlightened age of child study would seem unneces- 
sary of mention, but which unfortunately is still a factor in some 
instances, is the habit of deceiving the child as to what is to be done. 
There is no more fatal error, no more disastrous or appalling wrong, 
than to deliberately deceive a child, and the result of one such decep- 
tion can never be fully estimated. To the dishonor of some parents 
we are occasionally asked even in the beginning of the twentieth 
century to become a party to such an iniquitous practice, but no 
dentist of any self-respect or manhood will ever enter into such a 
conspiracy. It is always well, of course, to destroy in the-mind of the 
little patient any sense of fear by making as light as possible of the 
probable severity of the operation, and by the utmost tenderness and 
gentleness of demeanor; but to deliberately assure the child that a 
certain operation will not hurt in the least when it is almost certain 
to hurt, and worse than this to pretend to be applying some medicament 
to a tooth and then suddenly seize it with the forceps and extract it 
is a monstrous and cruel wrong. 

Ordinarilv the first visit of a child to the dental office should 



THE TREATMENT OF CHILDREN'S TEETH. 379 

be so managed, if possible, that no work of a disagreeable nature is 
undertaken. Mothers should be instructed to bring their children 
early, even before the necessity seems apparent, so that the child 
forms the habit of having the teeth examined and gets acquainted 
with the dentist. Thus, when fillings have to be made the ice is 
already broken and the way made easier. If the case has been deferred 
till toothache occurs, and the visit is one of necessity for relief, the 
only operative procedure undertaken at this time should be merely 
to stop the pain. A sympathetic and personal interest should be 
manifest for the little sufferer, and the impression formed at this 
first visit that the dentist is a kind hearted gentleman and not at all 
to be feared. When once confidence is attained it will usually be 
found that most children will tolerate any necessary discomfort in 
having their teeth cared for provided their pride is appealed to in 
the proper manner and they are upheld as little men and little women. 

But the dentist should have a care not to overtax the courage 
of a delicate child, and should constantly watch with the keenest 
eye for signs of wavering or undue nervous tension during an opera- 
tion. It is sometimes better to do temporary work and retain the 
confidence of the child than to always attempt permanent operations 
and thereby run the risk of creating distrust and dread. This is 
particularly true of operations on the deciduous teeth where the 
object is more to keep them comfortable for a few T years than to do 
artistic and permanent work. 

The materials for filling deciduous teeth are limited to those 
easy of insertion and not too exacting in their requirements. When 
cavities occur in the proximal surfaces of the incisors they are usually 
better managed with oxyphosphate of zinc than with anything else. 
They are ordinarily shallow, and the fact that they are frequently 
quite sensitive prevents the operator from giving them any appreciable 
retentive form. Cement can therefore be used when nothing else 
will remain in place. These teeth do not often call for much operative 
interference owing to their early loss to make way for the permanent 
incisors, but with the deciduous molars the case is different. They 
remain four or five years after the incisors are gone, and the problem 
of saving them when they decay is sometimes exceedingly difficult. 
They should be given early and frequent attention when the mouth 
is susceptible to caries, with the aim always of checking the disease 
and keeping the teeth comfortable for mastication. The reason 
for this is not only that the child shall be enabled to properly prepare 
the food for digestion during these early years, which of itself is very 



THE TREATMENT OF CHILDREN'S TEETH. 

important, but that proper habits of mastication are established at 
this impressionable age. If the deciduous molars are allowed to decay 
and become sensitive the child involuntarily forms the habit of bolting 
the food without proper mastication, and this habit once formed is 
likely to persist through life. There are many people today who do 
not masticate their food to the extent which their present masticating 
apparatus would warrant simply because they have formed the bad 
habit of bolting their food during youth. 

Simple cavities in the occlusal surfaces of these teeth are not 
difficult to manage. They may be rilled with oxyphosphate of zinc, 
oxyphosphate of copper, pink base-plate gutta-percha or amalgam, as 
is indicated in the individual case. Amalgam is more reliable than 
either of the others provided a proper preparation of the cavity may 
be made and it does not reach too close to the pulp, but sometimes 
we are obliged to temporize with cement or gutta-percha. 

The most difficult problem we meet in the management of de- 
ciduous teeth is to properly treat cavities occurring in the proximal 
surfaces of the molars. There are several factors in these cases 
tending to make them troublesome to control. They are usually 
sensitive, making them difficult of proper preparation for the reten- 
tion of amalgam, which is the only permanent material we have for 
preserving them. Unless fillings are reasonably well anchored in 
these cavities they are likely to be loosened by mastication, and if 
we attempt too deep anchorage we endanger the pulp. In fact 
these teeth do not usually present much area of tooth tissue in 
which to form a cavity and it takes but little penetration of decay 
to involve the pulp. It is always best to avoid irritating the pulp 
if possible, and to this end it is frequently advisable to use some other 
kind of material than metal to fill them. 

Much of the discomfort experienced by children in mastication 
is due to the packing of food in the interproximal spaces wherever 
decay has occurred in these surfaces. If cement is used it very rapidly 
wears away so as to present a space between the teeth and thus invite 
a lodgment of food. Not only this but frequently we find the teeth 
drifting slightly apart as the jaw expands preparatory to the eruption 
of the permanent teeth, all of which increases the difficulty. In cases 
where amalgam cannot be used and cement is unreliable the patient 
may be made more comfortable with gutta-percha than any other 
material, though this is, of course, more or less temporary in its service. 

The problem is greatly complicated where two cavities face each, 
other, and in some instances the surest method of making the teeth 



TREATMENT OF PERMANENT TEETH DURING CHILDHOOD. 38 1 

serviceable for mastication is to bridge across the interproximal 
space from cavity to cavity with gutta-percha. This is the only 
material by which two cavities may be joined in this way on account 
of the individual movement of the teeth. If a rigid material like 
cement or amalgam is used the filling will very shortly be loosened 
from one cavity or the other, but gutta-percha being more or less 
yielding will accommodate itself to the movement of the teeth with r 
out injury. If this plan is followed provision must be made to pre- 
vent the gutta-percha from being forced down between the teeth 
in the interproximal space, and this may be accomplished effectively 
by placing a metal guard of gold, platinum, or German silver across 
the interproximal space allowing the ends to rest on the gingival 
walls of the cavities and building the gutta-percha over it. This 
protects the gum most perfectly and admits of serviceable mastica- 
tion without discomfort. As the gutta-percha is worn away it may 
be renewed from time to time, and although this is at best a tem- 
porary operation yet it is in some of these troublesome cases the 
only procedure by which the teeth may be made serviceable. 

In pulpless deciduous molars the case should be treated in the 
usual way, except that some care should be taken not to introduce 
medicines which have a disagreeable taste or odor. It is always 
desirable with children to avoid as much as possible anything which 
tends to create prejudice against having dental operations performed, 
and usually these deciduous cases may be brought under control by 
the use of the essential oils which are less objectionable than some of 
the more powerful antiseptics. 

TREATMENT OF THE PERMANENT TEETH DURING CHILDHOOD. 

From the time the permanent teeth begin to erupt at about six years 
of age till the deciduous teeth are all lost and replaced by permanent 
ones at about twelve the care of the erupting teeth is a very important 
consideration, and in mouths where there is great susceptibility to 
decay of the teeth the problem of saving the permanent ones is some- 
times perplexing. 

When the incisors begin to decay in the proximal surfaces shortly 
after their eruption it is seldom that we can insert permanent fillings 
in them at once. It is, of course, better if this can be done, thus 
making one operation sufficient and creating in the mind of the patient 
the impression that dental operations are effective when properly 
performed. But there are many patients who lack the fortitude at 
such a tender age to go through the necessary tension to have thorough 



;S: THE TREATMENT OF CHILDREN'S TEETH. 

work performed, and it is better to make several operations on the 
one tooth at different times and preserve the courage of the child 
than to attempt a perfect piece of work at the outset and break the 
spirit of the patient, thus creating a dread of having dental work done. 

But let it be borne in mind that just so soon as it is found possible 
to have the temporary fillings replaced with permanent ones this 
should be done. In these susceptible cases the teeth can never be 
made too secure against decay even by the very best work the operator 
is capable of, and it is therefore well not to trust to temporary work 
longer than necessary. But in this connection it should be said that 
the attempt to use gold before the child is sufficiently under control 
to admit of doing a perfect piece of work will as certainly lead to 
failure as will the use of other materials more temporary in their nature. 
We must have a good technique in any operation calculated to be 
permanent and the requirements of gold in this respect are more 
exacting than for any other filling. In some instances we may employ 
inlay work in children's teeth before they will tolerate the exactions 
of gold foil filling and thus obtain a better result than by the use of 
any of the plastic materials. 

Each case should be studied carefully with the idea of learning 
the temperament of the child and knowing how to gain such control 
as shall permit of the best service. The practice of dentistry in its 
highest attainment is a constant study of conditions, conditions of 
the mind, conditions of the teeth, conditions of the surrounding 
parts — all of which materially affect us in the treatment of every 
case. And in this connection there is no other one thing of equal 
importance in the ultimate saving of the teeth and the maintenance 
of a healthy mouth than the establishment during these early years 
of the correct principles and practice of oral hygiene. It is not the 
province of the present chapter to go fully into this phase of the ques- 
tion, but it should be said in passing that no dentist is doing his full 
duty to the rising generation who fails to impress upon his young 
patients the importance of properly caring for the teeth and gums, 
or who does not give full instructions as to how this should be done. 
This should also be followed by a constant surveillance to see that 
his instructions are carried out. 

A very necessary consideration in the treatment of children's 
teeth is to watch carefully the condition of the first permanent molar. 
This tooth is one of the most important in the entire arch. It is the 
chief standard bearer of the jaws during the period when the de- 
ciduous teeth are being lost and the other permanent teeth are coming 



TREATMENT OF PERMANENT TEETH DURING CHILDHOOD. 383 

into place, and if lost early it invariably results in the jaws dropping 
closer together than normal which detracts materially from the force 
of character of the face. If it is lost subsequently to the eruption of 
the second permanent molar and the bicuspids it produces a tipping 
of the other teeth into the space so as to disarrange the occlusion. 
No arch is ever perfectly normal with the first permanent molar 
missing, and even in those cases where the space has entirely closed 
by the approach of the second molar and bicuspid and where the 
occlusion seems good from the buccal aspect it will be found defective 
if models are made and a careful examination is given the lingual 
aspect. 

In view of its early eruption it is peculiarly susceptible to decay, 
and should therefore be watched most carefully and preserved by 
filling. Where it has been extensively broken down by caries before 
it comes to the dentist it may usually be restored to full functional 
usefulness by the inlay method, and no pains should be spared to 
place it in a condition of health and service. 

As has already been stated, one of the chief functions of the dentist 
in his treatment of children is to educate them to the importance of 
properly caring for the teeth, and in respect of the first permanent 
molar it may be said that this education should begin with the parent 
before the child is of responsible age so that the frequent error of 
mistaking this tooth for a deciduous one and allowing it to go by 
default should not be committed. Parents should be instructed to 
bring their children to the dentist not later than the third or fourth 
year, and then the cooperation of the dentist, the parent and the child 
should result in every individual growing up with a good, serviceable 
set of teeth. 



CHAPTER XXV. 
LOCAL ANESTHESIA. 

BY HERMANN PRINZ, M.D., D.D.S. 

The elimination of pain during surgical operations is inseparably 
interwoven with the history of the human race. Forever it has been 
the aim of those interested in the cure of bodily ills to relieve pain 
in some empirical manner. These efforts, however, were seemingly 
so very futile that even as late as 1839 Velpau was led to express his 
pessimism as follows: "To escape pain in surgical operations is a 
chimera which we are not permitted to look for in our time." Little 
did he dream that he stood at the very threshold of the discovery of 
anesthesia, and that less than a decade later the Nirvana of painless 
operation would be an accomplished fact. 

The discovery of anesthesia is essentially to be credited to the 
dental and medical profession of the United States; the names of 
Crawford W. Long, Horace Wells, William T. G. Morton and Chas. 
T. Jackson are inseparably connected therewith. "If America has 
contributed nothing more to the stock of human happiness than 
anesthetics, the world would owe her an everlasting debt of gratitude." 
(S. T. Gross.) 

Anesthesia may be defined as an artificial deprivation of all sense 
of sensation, and, as a consequence, local anesthesia may be explained 
as the product of the same phenomenon in a circumscribed area of 
tissue. The mere absence of pain is referred to as analgesia. 

Local anesthesia may be produced by physical or chemical means. 
Physical means, as practiced in olden times, consisted primarily in 
nerve compression and the application of cold. The results were 
very problematic. At present, usually two definite ways are em- 
ployed to bring about local insensibility — first, the application of 
substances, topically or by hypodermic injection, which produce 
local anemia; and second, the hypodermic injection of drugs which 
act as inhibitors to the sensory fibers. 

Local anemia or ischemia, viz., a temporary constriction of cir- 
culation, prevents, as it has been experimentally shown, the rapid 
absorption of fluids which are injected into the affected area. The 
more important means applied for such purposes are: 

=5 38s 



386 LOCAL ANESTHESIA. 

1. The Esmarch elastic bandage. 

2. The application of cold. 

3. The extract of the suprarenal capsule. 

Some observers have maintained that local anemia as such produces 
anesthesia. This, however, is not the case. It is merely an important 
means to confine the injected anesthetic to the anemic region and 
thus bring about an increased and prolonged action of the drug, and 
also to enhance its deeper action. Consequently, the concentration 
of the anesthetic solution may be of a lower percentage, which of 
course lessens the danger of intoxication. 

For plausible reasons the Esmarch elastic bandage cannot be 
made use of for dental operations. 

Physically reducing the temperature of the body by the application 
of cold (ice pack, ice and salt mixture, cold metals, etc.) was practiced 
by the older surgeons. Through the efforts of Sir Richardson, in 
1866, this method was placed upon a rational basis by the intro- 
duction of his ether spray. To obtain good results, a pure ether 
(boiling point 95 F.) free from water is necessary. Certain other 
hydrocarbons possess similar properties in varying degrees, depending 
upon their individual boiling point. Within recent years, ethyl 
chlorid also known by many trade names, viz., antidolorine, kelene, 
narcotile, etc., and methyl chlorid and mixtures of the two in various 
proportions, known as anestol, anestile, coryl, metethyl, etc., are 
extensively use in minor oral and general surgery. A pure ethyl 
chlorid (boiling point 55 F.) is best suited for this purpose; 
it lowers the temperature of the tissues sufficiently to produce a short 
superficial anesthesia in a few minutes (it reduces the mercury of 
the thermometer to 50 F. below zero within 20 seconds). Too 
rapid cooling or prolonged freezing by methyl chlorid (boiling point 
— io° F.) or the various mixtures thereof produce deeper anes- 
thesia but such procedures are dangerous. They frequently cut off 
circulation in the affected part so completely as to produce sloughing 
(gangrene). Liquid nitrous-oxid gas, liquid or solid carbonic acid, and 
liquid air, all of which have a boiling point far below zero are recom- 
mended for similar purposes; they require cumbersome apparatuses 
and are extremely dangerous. 

Ethyl Chlorid. — Monochlorethane ; hydrochloric ether, C 2 H 5 C1. 
"A haloid derivative, prepared by the action of hydrochloric acid gas 
upon absolute alcohol." At normal temperature, ethyl chlorid 
is a gas, under a pressure of two atmospheres it condenses to a color- 
less, mobile, very volatile liquid, having a characteristic, rather agree- 



LOCAL ANESTHESIA. 387 

able odor and a burning taste. It boils at about 55 F. ; it is 
very inflammable, burning with a smoky green edged flame. It is 
stored in sealed glass or metal tubes and when liberated at ordinary 
room temperature (70 F.) it evaporates at once. In commerce 
it is supplied in plain or graduated glass tubes of from 3 to 60 
grams capacity or stored in metal cylinders holding from 60 to 
100 grams or more. To remove the ethyl chlorid from the her- 
metically sealed smaller tubes, the neck has to be broken off, while 
the larger glass and metal tubes are provided with suitable stopcocks 
of various designs to allow definite amounts of the liquid to be 
released. 

Mode of application: For the extraction of teeth, immediate 
removal of the pulp, opening of abscesses and other minor operations 
about the oral cavity the tube should be warmed to about 75 degrees 
by placing it in hot water and its capillary end should be held about 6 
to 10 inches away from the field of operation. The distance depends 
upon the size of the orifice of the nozzle; complete vaporization should 
always be produced. The Gebauer tube is fitted with a spray nozzle, 
which shortens the distance to one to two inches and is especially 
well adapted for dental purposes. The stream is directed upon the 
tissues until the latter are covered with ice crystals and have turned 
white. "For the extraction of teeth, the liquid should be projected 
directly upon the surface of the gum, as near to the apex of the root 
as possible, but care should be taken to protect the crown of the tooth 
on account of the painful action of cold on this part." Tissues to be 
anesthetized should be first dried and well surrounded by a film of 
vaseline or glycerin and protected by cotton rolls and napkins to 
prevent the liquid from running in the throat. Let the patient breath 
through the nose; occasionally light forms of general anesthesia are 
induced by inhaling the vapor. On account of the difficulty of direct- 
ing the stream of ethyl chlorid upon the tissues in the posterior part 
of the mouth, it is not successfully applied in those regions. The 
intense pain produced by the extreme cold prohibits its use in pulpitis 
and acute pericementitis. To anesthetize the second and third branch 
of the fifth nerve, it is recommended to direct the stream of ethyl 
chlorid upon the cheek in front of the tragus of the ear; the author 
has not seen any good results from such a procedure. Caution 
should be exercised in using ethyl chlorid near an open flame or in 
conjunction with the thermo-cautery; severe burns have resulted 
by setting the inflammable vapor on fire. 

Within the last decade the active principle of the suprarenal cap- 



3SS LOCAL ANESTHESIA. 

sule has demanded extensive comments in therapeutical literature. 
It has been isolated by a number of investigators under different 
names, viz., epinephrin by Abel (1897), suprarenin by Fuerth (1898) 
and adrenalin by Takamine and Aldrich (1901), and many other 
names are given to these compounds, viz., paranephrin, suprarenalin, 
hemostasin, etc., but we wish it to be understood that whenever we 
refer to adrenalin the hydrochlorid of the alkaloid of the suprarenal 
capsule is meant. Adrenalin is a grayish-white powder, slightly 
alkaline in reaction and in the dry form perfectly stable. It is sparingly 
soluble in cold, more soluble in hot water, insoluble in ether or alcohol. 
The preparation which is employed mostly for therapeutical purposes 
is a solution of adrenalin in physiological salt solution, 1 : 1000, to 
which preservatives, such as small quantities of chloretone, thymol, 
etc., are added. Adrenalin solutions do not keep well; on exposure 
to air they are easily oxidized, becoming pink, then red and finally 
brown. When this stage is reached the physiological property of the 
adrenalin is destroyed. When the solution is further diluted, it 
becomes practically worthless after twenty-four hours. When adre- 
nalin is injected into the tissues, even in extremely small doses, it tem- 
porarily raises the arterial blood pressure, acting as a powerful vaso- 
constrictor by stimulating the smooth muscular coat of the blood 
vessels and thus produces local anemia. Large doses finally reduce 
the blood pressure and heart failure results. The respiration at first 
quickly increases, but slows down and finally stops with the expiration. 
The action is largely confined to the peripheral vessels. Adrenalin 
is destroyed by the living tissue cells; the body rids itself of the poison 
in some unknown manner. While adrenalin does not possess local 
anesthetic action, it increases very materially the effect of certain 
anesthetics when they are injected into the tissues. This fact was 
brought out by Braun, of Leipsic, in 1902, who, by his classical re- 
searches brought local anesthesia to a rational basis. It is claimed 
that secondary hemorrhage frequently follows after the anemia pro- 
duced by the adrenalin has subsided and that the tissues themselves 
suffer from the poisoning effects of the drug, resulting in gangrene. 
Such results are only produced by the injection of too large quantities 
of the drug. The prolonged anemia will give way to a dilation of 
the blood vessels and if the tissues are too long deprived of circulation 
we are able to understand why sloughing will result. Small doses of 
adrenalin have no effect upon the tissues as such or upon the healing 
of a wound. Palpitation of the heart and muscle tremor which we 
occasionally notice when we first used this drug, were the direct 



LOCAL ANESTHESIA. 389 

result of too large doses. For dental purposes, viz., the injection 
into the gum tissue, the dose should be limited to i to 2 drops of the 
adrenalin chlorid solution (1:1000), diluted with one or more cubic 
centimeters of physiological salt solution. For ordinary purposes, one- 
half drop is quite sufficient. Concentrated solutions are dangerous, 
the injection of 6-8 drops diluted with 6 c.c. of a 1 per cent cocain 
solution has produced death in a weakly girl. 

According to more recent therapeutical conceptions it is generally 
recognized that a drug or combination of drugs which simultaneously 
produce local anemia and inhibition of the sensory nerves in a cir- 
cumscribed area of tissue is the logical solution of the question of 
local anesthesia. Certain important factors, however, relative to the 
physiological and physical action of the solution, employed for hypo- 
dermic injection, upon the cell govern the successful application of 
such methods. It is of prime importance, therefore, to comply with 
the laws regulating the absorption of injected solutions, viz., osmotic 
pressure. 

If we separate two solutions of salt of different concentration by 
a permeable membrane, a continuous current of salt and water results, 
which ceases only after equalization of the density of the two liquids, 
viz., equal osmotic pressure (according to Boyle-vant Hoff's law), is 
established. The current passes in both directions, drawing salt from 
the stronger to the weaker solution and water vice versa until osmotic 
equilibrium is obtained. The resultant solutions are termed isotonic 
(De Vries). In organized nature, these osmotic interchanges play 
an important factor in regulating the tissue fluids. The life of the 
cell depends upon the continuous passage of these tissue fluids, which 
furnish the nutrient materials, consisting of water, salt and albumin. 
These chemicals are normally present in certain definite proportions. 
A further important factor teaches us that all aqueous solutions 
which are isotonic possess the same freezing point. This law of 
physical chemistry has materially simplified the preparation of such 
solutions. The freezing point of human blood, lymph, serum, etc., 
has been found to equal approximately 0.55 C, which in turn 
corresponds to a 0.9 per cent sodium chlorid solution. Such a 
solution is termed a physiological salt solution. A slight deviation 
above and below the normal percentage of the solid constituents is 
permissible. When physiological salt solution is injected into the 
tissues in moderate quantities neither swelling nor shrinkage of the 
cell as such occurs; therefore, no irritation results, and in consequence 
no pain is felt. If, on the other hand, simple distilled water is injected, 



390 LOCAL ANESTHESIA. 

a superficial anesthesia only is produced; the injection itself is very- 
painful and acts as a direct protoplasm poison. 

With the introduction of cocain into therapeutics, local anesthesia 
achieved results which were beyond expectation, it opened new path- 
ways and it has robbed dental operations of their horrors. 

Cocain Hydrochloride — It is the principal alkaloid obtained from 
cocoa leaves (erythroxylon coca) a large shrub indigenous to tropical 
South America. It appears in colorless crystals, flaky, lustrous 
leaflets or white powder; it is odorless, has a saline, slightly bitter taste 
and produces when placed upon the tongue a tingling sensation fol- 
lowed by numbness. At ordinary temperature' it is soluble in about 
one-half part of water, about three parts of alcohol and glycerin, also 
soluble in chloroform, ether and olive oil. Its aqueous solution is 
neutral to litmus paper. Prolonged heating of the salt or its solution 
produces decomposition of the chemical into methyl alcohol, benzoic 
acid and ecgonin. Solutions of cocain are unstable, they should 
preferably always be made fresh when wanted. Cocain hydrochlorid 
is incompatible with alkali hydrates or carbonates, salicylates, ben- 
zoates, bromids and iodids, the mercury salts and silver nitrate. As 
early as i860, Niemann noted the fact that cocain when applied to 
the tongue produced local anesthesia; later investigations, especially 
those of Von Anrep (1879) were not fully appreciated until Carl 
Koller, of Vienna, later of New York, brought it before the medical 
profession in a paper read before the Congress of Ophthalmologists 
at Heidelberg in 1884. Cocain is a general protoplasmic poison, 
possessing a selective power for the sensory nerve elements. It 
paralyzes the nerve cells, fibers and endings and produces vasocon- 
striction at the place of its application. The respiration is at first 
accelerated, later it diminishes; respiratory paralysis is the usual cause 
of death. The pulse is quickened, later it is slow and weak; at first, 
the blood pressure rises, then falls and collapse results. Local 
anesthesia, according to Preyer's conception, is produced as follows: 
Cocain possesses a definite affinity for the living protoplasm of the 
nerve cell; it enters with it into a labile union, thus producing local 
anesthesia, which lasts until this temporary union is broken up by 
releasing the chemical, not as the original cocain, however, but as an 
inert compound of a simpler structure. In other words, the living 
tissues rid themselves of the poison in some unknown manner. In 
dead tissue, the injected cocain will suffer no change whatsoever. 

No direct antidotes of cocain are known, consequently the treat- 
ment of general intoxication is purely symptomatic. Recumbent 



LOCAL ANESTHESIA. 391 

position of the body and inhalation of a few drops of amyl nitrite are 
the first important steps in dealing with collapse, which should be 
followed in severe cases with small drops of nitro-glycerin and injection 
of strychnin sulphate, 1-30 of a grain, together with artificial respira- 
tion. 

The relative toxicity of a given quantity of cocain solution depends 
upon the concentration of the solution. Reclus and others have 
clearly demonstrated that a fixed quantity of cocain in a 5 per cent 
or 10 per cent solution is almost equally as poisonous as five times of 
the same quantity in a 1-5 per cent solution. From the extensive 
literature on the subject, we are safe in fixing the strength of the 
solution for dental purposes at 1 per cent. This quantity of cocain 
raises the freezing point of distilled water just a little above o.i° 
C. To obtain an isotonic solution corresponding to the freezing 
point of the blood, 0.8 per cent of sodium chlorid must be added. 
Having thus prepared a cocain solution which is equal to the blood 
in its osmotic pressure upon the cell wall, it is now necessary to aid 
the slightly vaso-constrictor power of the drug by the addition of a 
moderate quantity of adrenalin, thus increasing the confinement of 
the solution to the injected area by producing a deeper anemia, for 
the twofold purpose — first, to act as a means of increasing the anesthetic 
effect of cocain, and second, to lessen its toxicity upon the general 
system by slower absorption. As stated above, one drop of adrenalin 
added to 2 c.c. of the isotonic cocain solution is sufficient to produce 
the desired effect. 

A suitable solution for dental purposes may be prepared as follows : 



Cocain hydrochloric!, 


5 grains 


Sodium chlorid, 


4 grains 


Sterile water, 


1 fluid ounce 



To each syringeful (30 minims) add one drop of adrenalin chlorid 
solution, when used. 

Ever since the introduction of cocaine into materia medica for the 
purpose of producing local anesthesia quite a number of substitutes 
have peen placed before the profession, for which superiority in one 
respect or another is claimed over the original cocain. The more 
prominent members of this group are tropa-cocain, the eucains, 
acoin, nirvanin, alypin, stovain and novocain. None of these com- 
pounds with the exception of novocain has proven satisfactory for the 
purpose in view. The classical researches of Braun have established 
certain factors which are imperative relative to the value of a local 
anesthetic. The principal properties of such a chemical must cor- 



392 LOCAL ANESTHESIA. 

respond to the following claims: (i) In comparison to its local 
anesthetic value, it must be less toxic than cocain. The difference of 
toxicity must be absolute, viz., the quantity of the drug necessary to 
produce the same anesthetic effect as a definite quantity of cocain 
must be less toxic to the amount of body weight. (2) The chemical 
must be absolutely indifferent to the tissues when injected in more 
or less concentrated solutions. The progress of wound healing must 
not be interfered with by the solution. (3) The chemical must be 
readily soluble in water, the solution must be comparatively stable, 
and it should be possible to sterilize it by simple means. (4) The 
remedy must be tolerant to the addition of adrenalin without inter- 
fering with the vaso-constrictor power of the latter drug. (5) When 
applied to mucous surfaces ready penetration of the drug is necessary. 

Novocain has been recently (1905) discovered by Prof. Einhorn. 
It is a synthetical product, representing the hydrochlorid of para- 
aminobenzoyldiethylaminoethanol; it appears in colorless needle 
shaped crystals, readily soluble in one part of water and thirty parts 
of alcohol. Its solution may be boiled without decomposition; it 
reacts neutral to litmus paper. In general, it is incompatible with 
caustic alkalies and carbonates and the alkaloid reagents. Novocain 
possesses the same anesthetic power upon peripheral nerves as cocain. 
In one-quarter per cent solution it is sufficiently powerful to anesthe- 
tize even large nerves, viz. : it is equal in its anesthetic potency to any 
of the known local anesthetics. Pharmacologists (Biberfeld, Heineke 
and Laewen) have shown that novocain is about six to seven times 
less poisonous as compared with cocain. 

Novocain fully corresponds to every one of the above claims. Its 
toxicity is six to seven times less than cocain, it does not irritate in 
the slightest degree when injected, consequently, no pain is felt from 
its injection, per se; it is soluble in its own weight of water; it will 
combine with adrenalin in any proportion without interference of the 
physiological action of the latter and it will be readily absorbed by the 
mucous membranes. The studies of Biberfeld and Braun brought 
to light another extremely interesting factor concerning the novocain- 
adrenalin combination. Both experimentors, working independently 
of each other, observed that the adrenalin anemia on the one hand and 
the novocain anesthesia on the other hand were markedly increased in 
their total effect upon the tissues. Consequently a smaller quantity 
of this most happy combination is required to produce the same 
therapeutical effect as a larger dose of each individual drug would 
produce when injected separately. The injection of a solution of 






THE TECHNIQUE OF THE INJECTION. 393 

the combined drugs is precisely confined to the injected area; general 
effects are therefore rarely produced. 

As stated above, the relative toxicity of a given quantity of cocain 
in solution depends upon its concentration; this same peculiarity 
is not shared by novocain. The dose of novocain may be safely fixed 
at one-third of a grain for a single injection. For dental purposes, 
a 2 per cent solution is preferably employed; as much as 3 grains of a 
2 per cent solution in combination with adrenalin has been injected 
without any ill results. For the purpose of confining the injected 
novocain to a given area, the addition of adrenalin in small doses on 
account of its powerful vaso-constrictor action is admirably adapted. 
It is the important factor which prevents the ready absorption of both 
drugs and consequently nullifies poisonous results. An injection 
of ten drops of a 2 per cent solution of novocain labially into the gum 
tissue produces a diffuse anesthesia lasting approximately 20 minutes, 
the same quantity with the addition of a 1-1500 grain of adrenalin 
chlorid increases the anesthetic period to about one hour and localizes 
the effect upon the injected area. 

A suitable solution of novocain for dental purposes may be prepared 
as follows: 

Novocain, 10 grains 

Sodium chlorid, 5 grains 

Distilled water, 1 fluid ounce. Boil. 

To each syringeful (30 minims) add one drop of adrenalin chlorid 
solution when used. 

Ready made solutions of cocain and, to some extent, of novocain will 
not keep when frequently exposed to the air. A perfect sterile solu- 
tion may be made extemporaneously by dissolving the necessary 
amount of cocain or novocain in tablet form in a given quantity of 
boiled distilled water. A suitable tablet may be prepared as follows: 



Novocain, 


4 grain 


Adrenalin chlorid. 


T5V0 grain 


Sodium chlorid, 


1 grain. 



One tablet dissolved in 15 minims of sterile water makes a two 
per cent solution of novocain for immediate use. A small glass dish 
and a dropping bottle constitute the simple outfit. 

THE TECHNIQUE OF THE INJECTION. 

Various methods of injecting the fluid into the gum tissue are in 
vogue. For convenience sake, we may be permitted to divide them 
into: 



394 LOCAL ANESTHESIA. 

The injection about the root of a single tooth. 

The injection by infiltration near the gum fold. 

The injection into the hard tissue of the tooth, known as pressure 
anesthesia. 

Much of the success of the injection depends upon a good working 
hypodermic syringe, a fine sterile needle, a perfect technique of the 
injection, and last, but not least, a good sound judgment of the pre- 
vailing conditions. 

Before starting any surgical interference in the mouth, the field of oper- 
ration should be cleansed with an antiseptic solution. The syringe is 
filled by drawing the solution up into it ; invert the syringe and push the 
piston until the first drop appears at the needle point. This precaution 
prevents the injection of air into the tissues. The injection about the 
root of an anterior tooth is best started by inserting the needle mid- 
way between the gingival margin and the gum fold. Nothing is more 
dreaded by the patient than this first puncture; a small, very sharp 
needle causes very little pain. The pain may be entirely obviated 
by holding a pledget of cotton saturated with the prepared solution 
upon the gum for a minute or two or by applying a very small drop 
of phenol upon the point of puncture. The needle opening faces the 
bone, the syringe is held in the right hand at an acute angle with the 
long axis of the tooth while the left hand holds the lip and the cheek 
out of the way. After puncturing the mucosa, a drop of the fluid 
is deposited in the tissue, and further injection is painless. Slowly 
force the needle towards the apex of the tooth, depositing the fluid on 
its upward and return trip. The continuous slow moving of the 
needle prevents injecting into a vein. After removing the needle 
place the finger-tip over the puncture and exert slight pressure. A 
circular elevation outlines the injected area. No wheal should be 
raised by the fluid, it indicates superficial infiltration and consequently 
failure. As the liquid requires time to pass through the bone lamella 
and to reach the nerves of the pericemental membrane and the pulp, 
from five to ten minutes should be allowed before the extraction is 
started. The length of time depends upon the position of the tooth. 
The six anterior teeth usually require a labial injection only, the 
bicuspids and molars require both, a buccal and a lingual injection. 
For anatomical reasons, the lower molars present the greatest obstacles 
to a successful injection. It may be best accomplished by injecting 
the fluid buccally into the tissue near the gum fold, holding the syringe 
in a more horizontal position and lingually by using a curved needle. 
After anesthetizing the tissues buccally, the bone lamella may be 



THE TECHNIQUE OF THE INJECTION. 395 

penetrated by a small drill and the injection repeated through this 
drill hole. Occasionally it is possible to insert the needle between the 
tooth and the alveolar wall into the pericemental membrane. 

The injection into highly inflamed areas as we find in acute diffuse 
and acute purulent pericementitis is very painful; the engorged tissues 
will not tolerate a further infiltration, the fluid escapes into the mouth 
without producing any results. Careful infiltration of the sound 
tissues about the affected tooth by making a distal and mesial injection 
usually produces successful anesthesia. 

If two or more teeth are to be removed on one side of the jaw, 
the injection by means of infiltrating the area near the gum fold is to 
be preferred. It is advisable to use a one-half inch needle for this 
purpose, so as to reach a larger field with a single puncture. The 
fluid must be deposited under pressure close to the bone; the further 
procedures are analogous to the method as outlined above. 

By pressure anesthesia, pressure cataphoresis, pericemental 
anesthesia or contact anesthesia, as the process is variously termed, 
we understand the introduction of a local anesthetizing agent in 
solution by mechanical means through the dentin into the pulp for 
the purpose of rendering this latter organ insensible to pain. Simple 
hand pressure with a suitable instrument, the hypodermic syringe 
or the so-called high pressure syringe is recommended for such pur- 
poses. Before describing the modus operandi of the various methods, 
the histological structure of the dentin should be briefly recalled. 
Dentin is made up of about 72 per cent of inorganic salts, about ten 
per cent of water and an organic matrix constituting the remaining 
per cents. The dentin is perforated by a large number of tubules, 
radiating from the pulp cavity more or less wave-like towards the 
periphery, where they branch off forming a deltoid network. The 
dentinal tubules are filled with the processes of the odontoblasts and 
are known as Tomes' fibers. The odontoblasts form a continuous 
cover over the pulp. The dentinal fibrils are protoplasmic in their 
nature; normally, they do not carry sensation in the sense of the word 
as we understand this term as attributed to a nerve fiber; we can cut, 
file,. or otherwise injure sound dentin without the slightest inconven- 
ience to the patient. When the fibers have become highly irritated, 
the mere touch may at once produce a paroxysm of pain. 

Regarding the principles of pressure anesthesia, it should be remem- 
bered that we cannot force a liquid through healthy dentin by a me- 
chanical device without injury to the tooth itself. If a cocain solution 
is held in close contact with the protoplasmic fibers of the dentin, the 



396 LOCAL ANESTHESIA. 

absorption of cocain takes place in accordance with the law of osmosis. 
The imbibition of the anesthetic is enhanced by employing a physio- 
logical salt solution as a vehicle. On the other hand, living protoplasm 
reacts unfavorably against the ready absorption of substances by 
osmosis for two reasons: First, its albumin molecule is relatively 
large and not easily diffusible, and second, as an integral part of its 
life it possesses "vital" resistance toward foreign bodies. These 
latter factors are sufficiently demonstrated by the fact that it is almost 
impossible to stain living tissue. Dehydration of the protoplasm 
increase the endosmosis of the anesthetic solution markedly. 

When we apply the same "pressure" anesthesia upon carious 
dentin, the above statements do not hold good. We are able to press 
fluids quite readily through carious dentin. We must bear in mind 
that such dentin has been largely deprived of its inorganic salts, leaving 
an elastic spongy matrix in position. By drying out this dentin and 
then confining the anesthetic solution under a suitable water-tight 
cover, the pressure applied by the finger is quite sufficient to obtain 
the desired results. Colored fluids may be readily pressed through 
such dentin and even stain the pulp. 

In teeth not fully calcified and in so-called soft teeth, pressure 
anesthesia is more readily obtained while, according to Zederbaum, 
the process fails in "teeth of old persons, teeth of inveterate tobacco 
chewers, worn, abraded and eroded teeth, teeth with extensive secon- 
dary calcific deposits, teeth whose pulp canals are obstructed by pulp 
nodules, teeth with metallic oxides in tubules, teeth with leaky old 
fillings, badly calcified teeth — mainly all from one and the same 
cause, namely, clogged tubuli. In most cases no amount of persistent 
pressure will prove successful." 

From the foregoing it will be observed that the so-called high 
pressure syringes possess little merit relative to pressure anesthesia. 
The pressure which can be produced by a good working all-metal 
syringe, holding it between the index and middle fingers and forcing 
the piston with the thumb, amounts to 250 to 300 pounds in the average 
man. The pressure required in pressure anesthesia to produce a 
perfect contact is usually much less than the above force. 

METHOD OF ANESTHETIZING THE PULP. 

1. The pulp is wholly or partially exposed: Isolate the tooth with 
the rubber dam and clean it with water and alcohol. Excavate the 
cavity as much as possible and if the pulp is not exposed, dehydrate 
with alcohol and hot air. Saturate a pledget of cotton or a piece of 



METHOD OF ANESTHETIZING THE PULP. 397 

spunk with a concentrated cocain or novocain solution, place it into 
the prepared cavity and cover it with a piece of vulcanizable rubber 
and with a suitable burnisher apply slowly, increasing continuous 
pressure from one to three minutes. The pulp may now be exposed 
and tested. If it is still sensitive, repeat the process. Loeffler states 
that "this pressure may be applied by taking a short piece of orange 
wood, fit it into the cavity as prepared and direct the patient to bite 
down upon this with increasing force. In this way we can obtain a 
well-directed regulated force or pressure and with less discomfort 
to the patient and operator." Miller described this process as follows: 
"After excavating the cavity as far as convenient and smoothing the 
borders of it, take an impression in modeling compound, endeavoring 
to get the margins of the cavity fairly well brought out; put a few 
threads of cotton into the cavity and saturate them thoroughly with a 
five to ten per cent solution of cocain, cover this with a small bit of 
rubber dam and then press the compound impression down upon it. 
We obtain thereby a perfect closure of the margin, so that the liquid 
cannot escape and one can then exert pressure with the thumb suffi- 
cient to press the solution into the dentin." 

2. The pulp is covered with a thick layer of healthy dentin: With 
a very small spade drill bore through the enamel or direct into the 
dentin at a most convenient place, guiding the drill in the direction 
of the pulp chamber. Blow out the chips, dehydrate with alcohol 
and hot air and apply the syringe provided with a special needle 
making as nearly as possible a water-tight joint. Apply slow con- 
tinuous pressure from two or three minutes. With a round bur the 
pulp should now be exposed and if still found sensitive the process 
is to be repeated. 

Recently a method has come into vogue which allows successful 
anesthetization of the pulp by injecting the anesthetic solution around 
the apex of the tooth. The spongy alveolar process, which contains 
lymph channels, allows the ready penetration of the fluid. The 
injection should be made close to the bone pushing the needle slowly 
toward the apex while the fluid is deposited drop by drop. No wheal 
should be raised by the injection, otherwise the benefits of the pressure 
from the dense gum tissue is lost. 

According to Hertwig, the protoplasm of the cell primarily transfers 
irritation and secondly transmits absorbed materials. Therefore, the 
anesthetic solution has to pass through the entire dentinal fiber before 
the nerve tissue of the pulp proper is reached. Consequently a certain 
period of time is required before the physiological effect of the anes- 



398 LOCAL ANESTHESIA. 

thetic is manifested. This period of latency is dependent upon the 
thickness of the intermediate layer of dentin or bone. The successful 
anesthetization of the pulp depends largely upon this most important 
factor of allowing sufficient time for the proper migration and action 
of the drug. 

A good hypodermic syringe which answers all dental purposes 
equally well is an important factor in the successful techinque of the 
injection. The injection into the dense gum tissue frequently requires 
from 15 to 30 or even more pounds of pressure while in pressure 
anesthesia 200 to 300 pounds are often applied. After testing most 
of the dental hypodermic syringes and pressure instruments as offered 
in the dental depots within the last five years by means of the pressure 
gauge and in clinical work, subjecting the syringes to a routine wear 
and tear, we find that an all-metal syringe gives the best all-around 
service. It should hold about 30 minims. The Manhattan platinoid 
syringe can be recommended. If a glass syringe is preferred, the 
"Sub-Q" will answer the purpose. The hypodermic syringe requires 
careful attention. It is not necessary to sterilize it by boiling after 
each use unless contaminated with blood or pus; the simple washing 
with alcohol and careful drying is sufficient. The piston rod should 
be covered with a very thin film of carbolated vaseline. If the syringe 
is boiled, all the washers should be removed. Keep it in a covered 
glass or metal case; leather or felt lined boxes afford breeding places 
for bacteria. Dental hypodermic needles must be strong; they should 
be of re-enforced steel, 27 B. and S. gauge and provided with a razor 
edge point. The needle itself should measure a quarter of an inch. 
For infiltration anesthesia, one-half inch needles are necessary. Curved 
needles are often essential in reaching the posterior teeth. The 
"Schimmel" needles are excellent, they do not fit every syringe, 
however. For pressure anesthesia special needles are required. 
They may be bought at the depots or quickly prepared by grinding 
off the steel needle at its point of re-enforcement. The sterile needles 
should be kept in a well corked glass tube. They should be sterilized 
by boiling after each use in a 2 per cent lysol or cresol solution, dried 
with the hot air syringe and immediately transferred to a sterile glass 
tube. Sloughing resulting from an injection is, in the majority of 
cases, due to septic infection from a dirty needle. 

For reference to the administration of general anesthetics see 
chapter on The Extraction of Teeth. 



CHAPTER XXVI. 
THE EXTRACTION OF TEETH. 

BY FERDINAND J. S. GORGAS, A.M., M. D., D. D. S. 

The extraction of teeth, although usually regarded as a minor 
surgical operation, is, nevertheless, an operation that frequently pre- 
sents great difficulties, and is, perhaps, more often performed than 
any other in surgery. To successfully extract teeth requires an accurate 
knowledge of the histology, anatomy, and physiology of these organs, 
and the structures in direct relationship with them. The anatomy 
referred to, denominated "dental anatomy," includes that part of the 
science of organic structure which relates to the bones of the head, 
especially the jaws; the origin and distribution of the vessels and nerves 
supplying the dental tissues with blood and sensation; also a knowl- 
edge of the muscles concerned in moving the lower jaw, as well as 
those which are instrumental in producing the varied facial expressions. 

As the teeth are of dermal origin — morphological appendages of 
the skin, and compared with such tissues as hair and nails — the origin 
and development of their hard structures, viz., enamel, dentin, and 
cementum, should be well understood. 

The teeth, as before stated, being dermal appendages, are not a part 
of the osseous system, and the science of embryonic evolution teaches 
that they are inserted in sockets, as is common with all large teeth, 
and also that they have a strong attachment. In the human subject all 
the teeth are imbedded in well-developed alveolar cavities of the supe- 
rior and inferior maxillary bones, their function being to seize, bite, and 
masticate the food. 

The enamel is derived from the octoderm, differing in this respect 
from bone, which is a product of the mesoderm. The enamel cover- 
ing the exposed portion, or crown, of the tooth, being its protective 
covering, is the hardest structure in the body, and is not, like bone, 
regenerated. Its structural elements are enamel rods or prisms, and 
interprismatic or cement substance, which holds the rods or prisms 
together. When fractured, the tissue separates along the cemental 
line — this is known as the cleavage of the enamel. 

The dentin is derived from the mesoderm, and constitutes the body 
of the tooth, determines its form, and is similar, in respect to its origin, 

399 



400 THE EXTRACTION OF TEETH. 

to bono. The structural elements of the dentin are minute canals — 
tubules, and intertubular substance, the canals radiating from a central 
cavity which contains the pulp of the tooth. 

The cementum, which covers the root of the tooth and incloses the 
dentin, at the gingival border or neck of the tooth, slightly overlapping 
the enamel, is a variety of bone tissue, destitute, however, of the Haver- 
sian canals common to bone, but contains lacunae and canaliculi like 
bone. The cementum is composed of parallel lamellae of bone tissue, 
small vessels penetrating these thin plates, while other vessels, derived 
from the pulp, pass through the cementum in the opposite direction. 
Fibers from the investing membrane of the root of the tooth — per- 
icemental membrane, and which resemble the fibers of Sharpey in bone 
— are firmly attached to the cementum, and furnish a medium of con- 
nection by which the tooth is securely held in its alveolar cavity; they 
also account for the resistance offered by the tooth to its forcible re- 
moval by the forceps. 

The pericemental membrane lines the alveolar cavity and surrounds 
the root of the tooth. Its cellular elements are fibroblasts, osteoblasts, 
osteoclasts, and epithelial cells, the latter being located between the 
fibers of the membrane. 

The fibers of the pericemental membrane, formed and renewed by 
the fibroblasts, extend into the cementum and have a transverse direc- 
tion, being attached at one extremity to the cementum of the root of 
the tooth, and at the other to the bony wall of the alveolar cavity. 
Resembling Sharpey's fibers of bone, these fibers of the pericemental 
membrane are white and inelastic, their function being to increase and 
renew the fibrous tissue of the membrane by which the tooth is sup- 
ported in place. 

This fibrous tissue consists of two varieties, one of w T hich is coarse 
and radiating, and forms the bulk of the tissue, and by its strength 
firmly secures the tooth; the other variety is fine and interlaces with 
the coarse variety, being connected w T ith the blood vessels permeating 
the tissue. From the gingival portion of the cementum, the fibers of 
the pericemental membrane pass horizontally, some of them connect- 
ing with the membrane of adjoining teeth, and others passing into the 
connective tissue of the adjacent mucous membrane, thus giving hard- 
ness to the gums. The pericemental membrane is richly supplied 
with blood, some of the vessels entering the membrane near the apex 
of the root, others from the Haversian canals, while a third supply is 
derived from the mucous membrane of the gum near the gingival 
border. 



THE EXTRACTION OF TEETH. 



40I 



The teeth, being of dermal origin, are attached by insertion into 
well-developed cavities in the alveolar processes of the jaws, which are 
known as alveoli, and which are formed by the outer and inner plates 
of the alveolar process. The shape, size, and length of the 
roots of the teeth determine the shape, size and depth of the 
alveoli. (Fig. 274.) Each alveolus consists of compact bone tissue 
surrounded by cancellated or spongy tissue, which acts as a cushion 
against the shocks of mastication. The outer and inner plates of the 
alveolar process are connected by numerous septa which outline the 
shapes of the orifice of the cavities of the teeth. Dr. I. Norman 
Broomell, in his treatise on the " Anatomy and Histology of the 
Teeth," describes the alveoli as follows (Figs. 275, 276 and 277.): 
"The first socket, or that next to the mesial surface of the bone, gives 
support to the central incisor tooth. It forms almost a perfect cone, 




Fig. 274. 

and has an average depth of almost half an inch. Its lower border is 
circular, and the anterior or labial portion describes a larger circle than 
the posterior or palatal half. The mesial and distal walls are somewhat 
flattened. The second cavity proceeding backward from the mesial 
line, supports the lateral incisor tooth. It is also conic, but much 
smaller than the preceding. It is seldom over f to T \ of an inch in 
depth. It is much flattened on its mesial and distal walls, giving the 
appearance of an oblong, rather than a round cavity. This socket, 
as well as that for the central incisor occupies an almost vertical position 
in the process. Very frequently the socket for the lateral incisor 
presents a slight distal curve at its upper extremity. The third socket, 
or that giving support to the cuspid tooth, is much larger and deeper 
than those previously described. It extends upward, inward, and 
backward, to the average depth of § to f of an inch. In transverse 
section, its labial wall presents a much larger circle than its palatal 
26 



402 



THE EXTRACTION OF TEETH. 



margin. The labial and distal walls are much flattened and some- 
what convex. The general direction of this socket is to the distal. 
The socket which supports the first bicuspid is usually divided from 
mesial to distal by a thin septum of bone, thus forming an outer or 




Fig. 275. 

buccal socket, and an inner or palatal socket. This division seldom 
exists to the full depth of the cavity, but usually begins about midway 
of its length. The lower margin of this socket is oblong or egg-shaped, 
its outer or buccal portion forming a larger curve than its palatal. 




The lateral walls are slightly concave or flattened, until the point of 
separation is reached, when they become more circular, the alveoli 
above this point becoming cone-shaped. 

"It is not uncommon for this socket to be a single cavity, and when 



THE EXTRACTION OF TEETH. 403 

thus formed it resembles a flattened cone, with the buccal and palatal 
margins rounded. 

"The next socket gives support to the second bicuspid tooth, in most 
instances being a single cavity, but in rare instances it is divided near its 
upper extremity. In general outline it resembles the socket for the 
first bicuspid. The socket for the first molar is much larger than any 
of those previously described; its inferior margin presents a circular 
outline on its buccal and palatal portions, 
the former curve being larger than the 
latter. The mesial and distal walls are 
flattened and slightly concave. The 
upper three-fourths of this socket is 
divided into three separate compart- 
ments, being so arranged that two are 
on the buccal and one upon the palatal 
side. The septa separating the two 
buccal cavities from the palatal cavity 
are heavy and strong, while that placed 
between the two buccal sockets is thin 
and frail. The two buccal cavities are 
usually flattened upon their mesial and 
distal sides. The palatal socket is larger 
and somewhat deeper than the buccal, 
the average depth of all being about J an 
inch. 

"The socket for the second molar is 
similar in most respects to that for the first molar, except that it is 
somewhat smaller. The same description might answer for the third 
molar socket, which in general is similar to the alveoli for the other 
molars. It is smaller than the second molar socket, and may be a 
single cavity, or it may be divided into three or more compartments." 
(Fig. 275.) 

The average length of an upper central incisor root in the fraction of 
an inch is .49; of anupper lateral incisor is .5 1 ; of an upper cuspid .68 ; of 
an upper first bicuspid .48; of an upper second bicuspid .55; of an 
upper first molar .51; of an upper second molar .51; of an upper third 
molar .44; of a lower central incisor .47; of a lower lateral incisor .50; 
of a lower cuspid .60; of a lower first bicuspid .54; of a lower second 
bicuspid .56; of a lower first molar .52; of a lower second molar .50; 
of a lower third molar .36.* 

* These measurements are taken from Black's Dental Anatomy. 




404 THE EXTRACTION OF TEETH. 

The upper central incisor has a single root which is of conical form, 
its labial side more flattened than its lingual. The mesial and distal 
surfaces of this root are also somewhat flattened, and taper gradually 
from the base to the apex. The upper lateral incisor has also a single 
root, which is conical in form, and much more flattened from the mesial 
to the distal surfaces than the root of the central incisor. At the junc- 
tion of the root with the crown this root is circular in form, the labial 
portion forming the segment of a larger circle than the lingual portion; 
it is generally a straight root. The upper cuspid has also a single 
root, which is the largest and longest of any of the teeth; it is rounded on 
the labial and lingual surfaces, the labial forming the segment of a 
larger circle than the lingual. This root gradually diminishes in size 
from the neck of the tooth to its apex, and forms a perfect cone. The 
upper first bicuspid has usually two roots (although sometimes it has 
but one), which are quite similar in form. The buccal root, however, 
is usually a little longer than the lingual root, and both roots taper to 
slender apexes with an inclination to curve at their extremities. The 
point of bifurcation of these roots is usually some distance above the 
neck of the tooth. 

When this tooth has a single root, it is much flattened from the 
mesial to the distal surface, indicating a tendency toward the formation 
of two roots. The second upper bicuspid has usually a single root 
which is round on the buccal and lingual surfaces, and flattened on 
the mesial and distal surfaces. The upper first molar has three roots, 
two buccal and one lingual, the disto-buccal being the smallest, and 
more rounded than the mesio-buccal root. The lingual root is the 
largest and longest of the three roots, forming a long curve which ends 
in a sharp-pointed apex. The upper second molar has also three 
roots, two buccal and one lingual, which are much smaller than those 
of the first molar, and are more inclined to converge than to diverge. 
In general outlines they resemble those of the first molar. The root 
of the upper third molar, like the crown, is subject to a greater variety 
of form and number of roots, than any other tooth in the mouth. 
Normally it has the same number of roots as the two preceding molars, 
but sometimes as many as four or five are developed. Frequently, 
the three roots are so fused together as to present a single root with a 
line of demarcation between them, thus indicating by such an outline 
the character of the tooth. 

The lower central incisor has a single root which is usually smaller 
than that of any other tooth, and is flattened from the mesial to the 
distal surface, while its labial and lingual surfaces are rounded. The 



THE EXTRACTION OF TEETH. 405 

broad mesial and distal surfaces of this root, which is straight, taper 
gradually from the neck to the apex. 

The root of a lower lateral incisor is slightly longer, and larger, but, 
in other respects, is similar to that of the lower central incisor. The 
root of the lower cuspid is shorter and more flattened on its mesial 
and distal surfaces than that of the upper cuspid. Its labial and 
lingual surfaces are convex, and, like that of the upper cuspid, the 
labial forms the segment of a larger circle than the lingual. The root 
of the lower first bicuspid is usually single and straight, tapering grad- 
ually from the neck to the apex. Its buccal and lingual surfaces are 
convex, while the mesial and distal surfaces may sometimes be slightly 
convex, or flattened, and present a slight longitudinal concavity. The 
root of the lower second bicuspid is also single, and is larger and longer 
than the root of the lower first bicuspid, and its mesial and distal sur- 
faces are also similar. In some cases it tapers gradually from the 
neck to the apex, while in others its apex may be blunt and rounded. 

The roots of the lower first molar, two in number, situated imme- 
diately beneath the mesial and distal halves of the crown, are greatly 
flattened from the mesial to the distal surfaces, and each is broad at 
the neck from the buccal to the lingual surface. The mesial root is 
usually larger and longer than the distal root, the latter having a longit- 
udinal depression which renders it weaker than the mesial root. 
The distal root is generally straight, and gradually tapers from the 
neck to the apex, ending in a pointed extremity. The lower second 
molar has also two roots, a mesial and a distal, which are generally 
closer together than those of the lower first molar, and are less flattened 
upon their mesial and distal surfaces, and are more rounded, and taper 
more gradually from their necks to their apexes, which terminate 
in rounded ends. The roots of the lower third molars are normally 
two in number, like those of the lower first and second molars, but 
frequently a single conical root is presented; in other cases three roots 
may be developed, which are usually crooked and irregular, with a 
tendency to diverge from the crown. 

Under normal conditions, and if performed on scientific principles, 
tooth-extraction is not a difficult operation; although cases are some- 
times met with, where, owing to abnormal conditions, the operation 
requires considerable judgment and skill, severely trying the patience 
of the operator, and the endurance of the patient. It is therefore 
difficult to formulate special rules which may be literally followed. 
The axiom, which is. an established rule in all surgical procedures, 
that "every operation is performed quick enough that is performed 



400 THE EXTRACTION OF TEETH. 

well," is particularly applicable to tooth-extraction. A kind manner 
and a tender regard for the physical and mental suffering of the patients, 
on the part of the operator, will, in the majority of cases, so impress 
them, that they will quietly submit to his judgment and skill. It is 
well never to promise more than it is probable can be performed; and 
in the case of children, to adhere to the truth, for deception may render 
a first operation easy of accomplishment, but will react in the case of a 
second one, and leave such unhappy impressions upon the mind that 
years cannot entirely efface. 

Excessive solicitude should also be avoided upon the part of the 
operator, and in all cases patience and gentleness should be exercised. 
The unnecessary display of instruments, together with the preparation 
of them in the presence of the patient, should also be avoided. 

While it is true that the most expressive lamentations by the patient 
do not invariably indicate acute suffering, yet there are other cases 
where no outward manifestations of pain may be exhibited, and at the 
same time the effect on the nervous system be such as to severely tax 
the vital energy. Hence it is better not to exact too much of a nervous 
patient, who may heroically nerve herself to quietly endure intense 
suffering, and show no visible signs of agony. 

The question as to "whether or no a tooth is to be extracted" may 
be answered as follows: " When a tooth or a part thereof can be made 
of no further use to the patient, or when its retention cannot be ac- 
complished with comfort to its possessor, or when its presence prevents 
the correction of more important teeth, it should be extracted." Such 
an answer may embrace all indications for this operation. On the 
other hand certain conditions which have been termed "contra- 
indications" against tooth-extraction have been advanced with more 
or less reason. The following are the more important: The avoidance 
of such an operation during the periods of menstruation, gestation, and 
lactation, as it may seriously interfere with these functions. The 
more prominent of these contra-indications, however, is the condition 
of pregnancy, as the shock of such an operation as tooth-extraction 
may, it is asserted, cause miscarriage at certain periods of its existence. 

The term "abortion" signifies the expulsion of the product of 
conception from the womb before the end of the 7th month, and is 
the great accident of pregnancy. 

It is most liable to occur during the 3rd, 4th, and 5th months 
of gestation, for the reason that at these periods, there is no adhesion 
between the ovum and uterus. As soon as the chorion and the decidua 
are developed, separation of these organs becomes more difficult, and 



THE EXTRACTION OF TEETH. 407 

miscarriage is not so prone to occur; hence, the danger of such an ac- 
cident diminishes as gestation advances. 

When it is absolutely necessary to extract a tooth at a certain period 
in this condition, and palliative measures have failed to give relief, 
and extraction will prove to be a lighter tax upon the patient's vital 
powers than a severe and prolonged attack of toothache, and especially 
if a proneness to abortion exists, the family physician should be con- 
sulted, and the dental practitioner be governed by his opinion. The 
pathological conditions of the uterus which predispose to abortion, 
comprise all that interfere with the development of the ovum, such as 
displacement, inflammatory affections of the lining membrane, uterine 
tumors, disease of the ovaries, rectum and bladder; the most common 
causes of abortion are to be found in the ovum. An affection which 
has been regarded as another contra-indication is hemophilia (hemor- 
rhagic diathesis). This condition is characterized by severe bleeding 
from trivial injuries, and is generally hereditary, and transmitted 
through the females to their male decendants. It is due to a decrease 
of coagulability in the blood; also to changes in the vessels, such as may 
be caused by disease, the vessels becoming so weak so to be unable to 
withstand the normal pressure. Hemophilia may occur during the 
course of scurvy, purpura, leukemia, etc. When such a diathesis is 
present, proper measures should be resorted to for controlling the 
heart's action and increasing the coagulability of the blood, such as the 
administration of acetate of lead in two grain doses every two hours, 
or nux vomica, or aconite, or digitalis, or gallic acid, or chlorid of iron, 
or the following formula: 

1$ — Infusi digitalis, §ii 

Ext. ergotae, fluidi, 

Tincturi of krameriae, aa §j 

Dose: — A tablespoonful as required. 

Also such styptics for application to the bleeding cavity, as adrenalin 
chlorid, tannic acid, antipyrin, chloride of iron, powdered subsulphate of 
iron, orthoform, etc. Extreme debility and nervous depression have 
also been regarded as contra-indications against tooth-extraction, 
the latter often resulting from dread of the operation. The pain of 
an aching tooth may sometimes aggravate the symptoms of an existing 
disease, or may at least retard recovery, when sedative treatment is 
indicated, such as the administration of bromid of potassium, or 
sodium, valerianate of ammonia, etc., with tonics. 

The condition of the membranous tissue of the mouth must also 
be considered, such as erysipelatous inflammation, for example, 



408 THE EXTRACTION OF TEETH. 

owing to its tendency to spread so as to involve the glands and throat, 
as a result of tooth-extraction. The nervous affection known as epi- 
lepsy, characterized by convulsions and loss of consciousness, the 
existence of which is generally made known by the patient prior to the 
operation, has also been named as one of the contra-indications 
against tooth-extraction; but from the fact that proper precautions can 
be taken to guard the patient against any injury occurring to him during 
the existence of the paroxysm, this affection need not prevent the per- 
formance of the operation. 

The extraction of the deciduous teeth requires so little force, 
owing to the degree of physiological absorption of both their roots and 
alveolar processes at the period when their removal is required, that 
it may be considered a simple procedure. Care, however, must be 
taken not to injure the developing permanent teeth located directly 
under the deciduous ones. The greatest difficulty met with is the 
task of gaining the consent of such young patients. A false promise 
not to hurt will destroy the confidence of the patient in the veracity 
of the operator, and what the latter may gain by deception at one 
operation will only increase the difficulty at a subsequent one. The 
most important matter connected with the extraction of the deciduous 
teeth, is for the operator to possess an accurate knowledge of the 
order in which nature proposes to replace these teeth with the per- 
manent ones; for in no instance will any interruption with this order 
be tolerated, without such results occurring as the irregular arrange- 
ment of the teeth of the permanent set. The following is the order of 
eruption of both the deciduous and permanent teeth: 

DECIDUOUS TEETH. PERMANENT TEETH. 

Central incisors 5 to 8 months First molars 5 to 6 years 



Lateral incisors 7 to 10 " 


Central incisors 6 to 8 


First molars 12 to 16 " 


Lateral incisors 7 to 9 


Cuspids 14 to 20 " 


First bicuspids 9 to 10 


Second molars 20 to 36 " 


Second bicuspids 10 to 12 




Cuspids n to 13 




Second molars 12 to 14 




Third molars 17 to 21 



The first step in the operation of tooth-extraction is to make a care- 
ful examination to determine the location and condition of the tooth 
to be removed, its relations to the adjoining teeth, and the general 
state of the mouth; and, if an anesthetic agent is to be employed, the 
systemic condition of the patient. 

The second step is to select the proper instruments to be used during 
the operation. The third step is to determine the direction in which the 



THE EXTRACTION OF TEETH. 409 

force it is necessary to employ can be applied in the line of least re- 
sistance, owing to the difference in anatomical structure, the number 
of roots, the class of tooth, and the position of the tooth in the alveolar 
arch. 

The operation itself may also be divided into three stages: i. The 
application of the forceps in order to secure a firm hold on the tooth 
to be removed, which is usually the upper part of the cervical portion 
or neck (Fig. 274), so that the edges of the beaks of the instrument may 
be forced between this part of root and the margins of the alveolus; 
for by thus opening the orifice by expansion, or by a slight fracture of 
these edges, the removal of a normally formed tooth is greatly facilitated. 

2. The application of the required degree of force by which the 
pericemental attachment of the tooth with its alveolar cavity is loosened. 

3. The careful removal of the loosened tooth from its cavity, and 
from between the jaws and over the lips, in a manner that will prevent 
injury to the adjacent teeth, and laceration of the lips by the ragged 
decayed tooth crown; or by the loosened tooth suddenly leaving its 
cavity, as in the case of a lower tooth, and the forceps fracturing another 
in the opposite jaw. Hence, the lips of the patient, as well as the 
fingers of the left hand of the operator holding the lips open, should be 
protected by a napkin. Each stage of the operation should be com- 
pleted before beginning the succeeding one, and no movement be made 
by the forceps more rapidly than the eye can follow. In performing 
this operation, the object should be the removal of the entire tooth, with 
as little mutilation of surrounding soft tissues as is possible. The 
application of three forces is usually regarded as necessary in ex- 
tracting, namely traction, rotation, and pressure; "traction" is de- 
fined as the drawing force, "rotation" is the turning around on an 
axis or center; "pressure" is the force exerted by one body on another 
— applied to this operation, it is the force used on a tooth when raising 
and pushing it from its cavity. 

Position oj Operator and Patient. — The position of the operator in 
performing this operation, and also that of the patient, should depend 
upon the teeth to be extracted — whether upper or lower teeth; whether 
the teeth are on the right or the left side of the mouth. For extracting the 
upper teeth, the operator should occupy a position on the right side of 
the patient, whose head should rest in the depression of the head-rest 
of the dental chair, the back of which should be lowered at about an 
angle of forty-five degrees. In such a position the head of the patient 
is thrown well back, being encircled by the left arm of the operator 
which rests on the edge of the head-rest, thus giving the head a firm 



4IO THE EXTRACTION OF TEETH. 

support by pressure against his breast. The fingers of his left hand 
arc used to distend the lips of the patient, and also to retain a napkin 
in place, so that injury of the lips may be prevented while the de- 
tached tooth is being removed from between them. 

For extracting the upper teeth on the right side, the position of the 
operator should be to the right and a little to the front of the patient, 
who is seated in the dental chair, with an observance of the directions 
already given. For extracting the upper teeth on the left side, the 
position of the operator should be on the right and a little more 
to the front of the patient, than for the teeth on the right side. 
For extracting the lower teeth, the operator should occupy a posi- 
tion on the right, but more toward the rear, of the patient, with the 
palm of his left hand pressed against body of the lower jaw over the 
cheek, his fingers over the body of the lower jaw, and his thumb de- 
pressing the lower lip, and assisting in supporting the jaw. The 
back of the dental chair, which is lowered, should be almost vertical, 
permitting the patient to assume a more upright position. A small 
stool for the operator placed to the rear of the chair, will enable him 
to overreach the head of the patient, and permit his having more com- 
mand of his right arm and wrist. 

For the successful removal of both upper and lower teeth, it is 
necessary that the head of the patient should be so firmly supported 
that the entire force exerted by the operator should be borne by the tooth, 
and this force so controlled as to prevent injury, either to the adjoining 
teeth, or to those in the opposite jaw, by a loosened tooth suddenly 
leaving its cavity. 

Instruments Employed for the Extraction oj Teeth. — The instru- 
ments employed for the extraction of teeth are forceps, elevators, and 
the screw. There are special recognized forms of forceps adapted to 
the different classes of teeth, and also other forms which are applicable 
to teeth presenting abnormal shapes of both crowns and roots. Per- 
haps the best rule to follow is for the operator, after some experience, 
to employ those forms with which he is the most successful. 

The early dentists employed very uncouth instruments for extract- 
ing teeth, and the now almost obsolete turnkey of Garengeo was con- 
sidered to be a great improvement on the extracting instruments that 
preceded it. This instrument, the use of which has been productive of 
many serious accidents, consists of either a straight or bent shaft, and 
two or more hooks, with a bolster to rest upon the inner surface of 
the gums over the alveolar cavity of the tooth to be extracted, which 
forms the fulcrum. After the use of the lancet so separate the gums, 



THE EXTRACTION OF TEETH. 411 

the pointed beaks of the hook are firmly attached to the outside sur- 
face of the neck of the tooth, the handle of the key grasped firmly with 
the right hand, and the tooth raised from its cavity by a firm and 
steady rotation of the wrist of the operator. With the improved 
instruments used at the present time, the direction of the force is in 
the line of the axis of the tooth, while that of the key is made in a lateral 
direction only. 

To perform the operation of tooth-extraction successfully, the 
operator should be provided with forceps of the best quality, so well 
tempered that the beaks will spring instead of fracture under the force 
to which they are subjected, and so shaped as to permit of accurate 
adjustment without interfering with the adjoining teeth. The beaks 
should also be so curved as to overreach the crowns of the teeth when 
their edges are applied to the necks, and thus avoid fractures of the 
crowns; and so thin and sharp that the use of the gum lancet may 
be dispensed with in most cases, and permit of the edges of the 
beaks being introduced between the gum margin and the thin walls 
of the orifices of the alveolar cavities. A badly adapted forceps 
presents to the surface to which it is applied but one or two 
points, which prevent the application of the necessary traction. 
The handles of these instruments should be wide, and of such a 
form as will fit the hand of the operator, be perfectly rigid when 
firmly grasped, and serrated on their outer surfaces to prevent slipping 
through the hand. A curve on the end of one of the handles is adapted 
to the little finger of the hand holding the instrument, and materially 
assists in applying the required force in the case of firmly implanted 
teeth. The manner of applying and using the forceps may be 
described as follows: The forceps is firmly grasped in the right 
hand with the palm of the hand inward and the thumb on the top, 
with its ball pressed between the handles in the bifurcation, with such 
force as will regulate and limit the pressure of the beaks after their 
edges are applied to the portion of the tooth at the neck to be grasped. 
By using the ball of the thumb in the manner described an increase of 
the pressure, to a greater degree then is necessary, on the tooth may be 
avoided without incurring the danger of crushing it. 

The first or second finger (according to their length) of the hand 
holding the forceps should be inserted between the handles near the 
bifurcation, and employed for separating the beaks, and also to assist 
in maintaining a firm hold on the instrument. The little finger of 
the right hand is applied to the curved end at the extremity of the 
outer handle of the forceps, and, with the serrated outer surface 



41 ? 



THE EXTRACTION OF TEETH. 




THE EXTRACTION OF TEETH. 413 

of the handles, will prevent the instrument from slipping through 
the hand. The inner beak of the forceps, when applying it to 
the neck of the tooth, should be placed in position first, then the 
outer beak, care being taken to keep these beaks clear of the crown of 
the tooth, and thus avoid its fracture; then, according to the class of 
tooth, rotation, or the outward and inward motions are made to break 
the attachment of the tooth to its alveolar cavity. In some cases, 
especially of frail roots, it may be necessary to apply forceps with cut- 
ting-edged circular beaks to the outside of the outer and inner walls 
of the alveolar cavity and cut through such walls, in order to obtain a 
firmer hold on the stronger portions of such roots. What is termed " a 
cultivated sense of touch" is soon acquired by the operator, when the 
loosening of a tooth by rotation, or the outward or inward motions 
(according to the class of tooth) becomes at once apparent; or its 
yielding in one direction only, when a change in the application of the 
traction may secure its removal from its cavity with slight effort. 
Cases have occurred in the practice of the writer where a firmly im- 
planted cuspid tooth has resisted all efforts to remove it, to such a degree 
as to render it dangerous to apply greater force, when the postponement 
of the operation to the following day has resulted in its easy extraction, 
owing to the effects of the inflammation excited in its investing mem- 
brane by the previous attempt. 

After applying the beaks of the forceps to the neck of the tooth, 
they should not be pressed together more tightly than is necessary 
for securing and maintaining a firm hold ; otherwise there is danger of 
fracturing the tooth. 

Considering the different classes of teeth, the following rules may be 
formulated for their removal with the forceps: Beginning with the 
upper central and lateral incisors, which may be grouped together 
on account of the similarity of their roots and environment, the force 
for loosening these teeth should first be applied in the direction of a 
line drawn through the greatest axis of the tooth at the same time using 
rotation, as these are single rooted teeth of conical form; should any 
portion of the alveolar walls of their cavities be in danger of removal 
by the strong adhesion of their roots, the rotary motion will loosen it. 

In all cases the pressure applied should be labial, for the reason 
that it is in the line of least resistance, the alveolar process on the labial 
aspect being thinner than on the lingual; another reason is that pres- 
sure toward the lingual causes more pain. Labial pressure, when not 
excessive, will enlarge the orifice of the alveolar cavity, without the 
danger of fracturing the margins to any degree. (Fig. 278.) 



414 



THE EXTRACTION OF TEETH. 







THE EXTRACTION OF TEETH. 



415 




ft 
ft 

D 




41 THE EXTRACTION OF TEETH. 

For the extraction of the upper cuspids a considerable degree of 
traction is usually necessary, more, perhaps, than for any other teeth, 
as these teeth have the longest roots, and are, as a rule, firmly implanted 
in their cavities. The traction applied should be in the labial direction, 
as this is in the line of least resistance, and as soon as an impression 
is made, and the tooth slightly loosened by such force, then slight rota- 
tion will assist in displacing it; the rotary motion will also tend to 
detach any portion of the process which may adhere to the root, as 
this is by no means an uncommon occurrence. The rotary movement 
should be applied in such a manner that the labial portion of the tooth 
is moved toward the median line, from the fact that the root of this 
tooth frequently has a direction backward. (Fig. 279.) For the ex- 
traction of the upper bicuspids, traction is generally employed. In 
the case of the upper first bicuspid, the force employed should be 
limited in degree, as this tooth has usually two slender roots and the 
process over the buccal root is thicker than over the root of the cuspid, 
hence, there is danger of fracturing this root if great force is employed. 
On this account the force should be carefully applied, and in the lingual 
direction to a greater degree than in the buccal direction. The second 
upper bicuspid has usually a single root which is round on the 
buccal and lingual surfaces, and flattened on the mesial and distal 
surfaces, the root being disproportionately long compared with the 
circumference of the neck. For the extraction of this tooth, traction 
may be applied in the line of least resistance, which is the buccal — 
that is according to its outward inclination, and when slightly loosened, 
the rotary motion may be resorted to completely displace the tooth. 
(Fig. 280.) For the removal of the upper first and second molars, 
which may also be grouped together on account of similarity in form, 
position and environment, traction should be applied first in a buccal 
direction according to the outward inclination of the tooth, for the 
reason that the resistance is first offered by a single or lingual root, 
and when an impression is made upon this root, that of the two buccal 
roots, the smaller ones, is soon overcome, and a slightly rotary motion, 
although the roots may diverge to a degree, will displace the tooth; 
the process is also thinner on the buccal aspect than on the lingual. 
Care should be taken, however, not to make the buccal pressure too 
great, for in such a case considerable fracture of the buccal wall of the 
process may result. (Figs. 281, 282, 283 and 284.) For the extraction 
of the upper third molars, traction should be made downward and back- 
ward. The roots of this tooth are frequently so fused together as to 
present but one of an irregular form, which permits the use of the rotary 



THE EXTRACTION OF TEETH. 



41 




4iS 



THE EXTRACTION OF TEETH. 







THE EXTRACTION OF TEETH. 419 

motion in the direction of the raphe at the median line of the hard 
palate or roof of the mouth. These teeth being the last in the upper 
arch, and near the tuberosity of the process, are not usually very firmly 
implanted, especially as the alveolar process surrounding the distal 
surfaces of their necks is but imperfectly developed. Hence care 
should be taken that a tooth of this class, when loosened by the forceps, 
does not escape from the instrument, and slipping down the throat 
enter the larynx (Fig. 285) . It is not unusual for the upper third molars 
to erupt on the outer side of the alveolar ridge with their occlusal sur- 
faces directed toward the cheek; in such cases the direction of the force 
should be outward and upward, and the mutilation of the tuberosity 
be avoided on the account of the danger of penetrating the antrum, 
and also of injuring the vessels and nerves passing through the tuberos- 
ity in this locality. As the gum tissue at the distal surface of these 
teeth often adheres strongly to the neck, it is better to employ the gum 
lancet to sever the connection, and thus avoid the danger of tearing the 
gum. The form of lancet represented by Fig. 301 (3) answers for 
such cases. 

The lower teeth are usually more difficult to extract than the upper 
ones, especially the lower third molars when partly erupted or impacted, 
owing to the space between the second lower molar and the ascending 
ramus of the jaw not being sufficient for their accommodation; such a 
difficulty may be greatly increased when the patient is unable to open 
the mouth to any extent owing to the inflammation incited by the tooth 
itself in the adjacent tissues, or by other pathological conditions, such 
as alveolar abscess for example. The fact that the inferior maxillary 
bone is a movable one, also adds to the difficulty of extracting the lower 
teeth, as it is necessary for the operator to hold the jaw immovably, 
by placing the palm of his left hand over that portion of the cheek 
covering the body and border of the bone, his fingers under the jaws, 
and his thumb pressing down the lower lip, and also assisting in sup- 
porting the jaw. 

The external oblique line extending across the outside surface of 
the lower jaw, from near the mental process to the base of the ramus, 
and the mylo-hyoid ridge on the inner surface of this bone, which extends 
from a point near the base of the bone at the median line, and passes 
backward and upward to the base of the ascending portion, giving 
origin to the mylo-hyoid muscle which forms the greater part of the 
floor of the mouth; both of these prominences add to the thickness 
of the alveolar ridge over the roots of the lower molars, and increase 
the difficulty of extracting them; this is especially the case with the 



4 2 ° 



THE EXTRACTION OF TEETH. 




THE EXTRACTION OF TEETH. 



421 




42 2 THE EXTRACTION OF TEETH. 

lower third molars, when their roots curve posteriorly, or these teeth 
are but partly erupted, or impacted. 

For extracting the lower central and lateral incisors and cuspids, 
these teeth having single, straight and mesio-distal flattened roots, the 
operator in removing them occupies a position a little back on the right 
side of the patient, who is seated more uprightly in the dental chair 
than for the removal of the upper teeth. A narrow beaked forceps 
is employed for the removal of the lower central and lateral incisors, 
such as are represented by Figs. 286 and 287, and the outward and in- 
ward motions are applied with a force sufficient to expand, but not to 
fracture to any degree, the orifices of their alveolar cavities. 

The lower cuspids, being larger teeth, and more firmly implanted 
than the lower incisors, require stronger forceps for their removal; 
hence, the lower bicuspid forceps, represented by Fig. 288, is generally 
employed. For extracting the lower first and second bicuspids, which 
have generally but a single root, which is straight, tapering gradually 
from the neck to the apex, that of the second being larger and longer 
than that of the first bicuspid, the motion required should be out- 
ward and inward, accompanied with a slight rotary motion as the tooth 
is yielding, to assist in detaching the process from the root. (Fig. 289.) 
For extracting the lower first and second molars, the outward and 
inward motions should be made ; the roots of these teeth, two in num- 
ber, usually diverge and stand across the alveolar ridge, being situated 
immediately beneath the mesial and distal halves of the crowns. 

They are flattened on their mesial and distal surfaces, and broad 
at the neck from the buccal to the lingual surfaces; the mesial root usu- 
ally being somewhat larger and longer than the distal root. The instru- 
ments adapted for their removal are illustrated by Figs. 290 and 291. 
The points on the concave edges of beaks of this forceps should be 
inserted in the space between the roots on each side of the alveolar 
ridge, the concave surfaces grasping the convex surfaces of the roots. 
Care should be taken when applying the forceps that no part of the 
tongue be inclosed between the beaks and the roots; the danger of a 
lower molar suddenly leaving its cavity after being loosened, and the 
forceps fracturing teeth in the opposite jaw should be guarded against. 
Some prefer to apply the first force, in loosening these teeth, in the 
direction of the inclination of the tooth in its cavity, either outward or 
inward. When the two roots of a lower molar diverge greatly it may 
become necessary to use the splitting forceps represented by Fig. 292, 
the sharp edges of which are carried down over the crown to the space 
between the roots, and the crown divided at the center of the buccal 






THE EXTRACTION OF TEETH. 



423 





4-M 



THE EXTRACTION OF TEETH. 



and lingual surfaces, using a strong pair of root forceps to remove each 
root thus separated. The extraction of a lower second molar is 
usually an easier operation than that of a first molar, for the reason 
that the roots of the second do not diverge from the neck to the same 
degree. The extraction of the lower third molar, when the teeth 
occupying the arch are not unusually large, or irregular in position, is 
not difficult and can be accomplished by the forceps represented by 
Fig. 293. The outward and inward motions are usually employed for 
loosening the lower third molars, except in cases where, owing to 





Fig. 204. — Deciduous Teeth Forceps. 



irregularity in position, it may be better to apply the first force accord- 
ing to the outward or inward inclination of the tooth. 

The operator and patient occupy the same positions in the extrac- 
tion of both the lower first and second molars. When the force it 
would be necessary to use in attempting to extract an abnormally 
shaped, or located lower third molar would endanger the bone of the 
jaw, and especially when there is a backward curvature of the root, 
it is better to cut away the process with a bone-cutting bur, operated 
by the dental engine, until a sufficient portion of the root is exposed 
to be grasped by the forceps; this method can also be followed in the 
case of hypercementosed roots of other teeth; also in cases of partly 



THE EXTRACTION OF TEETH. 



42 5 



P3 



H 












11 



X 



426 



THE EXTRACTION OF TEETH. 




THE EXTRACTION OF TEETH. 



427 



erupted, and impacted teeth. In loosening abnormal lower third 
molars, the direction of the force applied should be outward, backward, 
and upward. What is known as the elevating forceps is also employed 
for the extraction of partially erupted lower third molar teeth, the 
pointed ends of the beaks being applied in the space between such a 
tooth and the second molar, the latter tooth being used as a fulcrum. 
When a secure hold is obtained, the handles of the instrument are 
depressed and the abnormally placed tooth is forced from its cavity, 
or so loosened that it can be readily seized with the root forceps. 
After extracting any class of tooth, the expanded margins of the alveolar 









Fig. 299. 



cavity should be gently pressed together with the thumb and forefinger. 
As a preventive against hemorrhage, and the after-pain of extraction, 
it has been recommended to fill the cavity from which the tooth has 
been removed with powdered orthof orm, or to apply a solution of phenol 
sodique on a pledget of cotton. 

The Extraction of Deciduous Teeth. — The extraction of the decid- 
uous teeth is performed in the same manner as those of the permanent 
teeth, smaller and fewer instruments, however, being required. Fig. 
294 represents a set of three forms of small forceps suitable for the re- 
moval of the deciduous teeth, although many operators employ the 



428 



THE EXTRACTION OF TEETH. 



smaller beak forceps of the permanent teeth instruments, especially 
the root -forceps for the removal of such teeth. Less force is required 
for the extraction of the deciduous teeth for reasons before given, but 
it is necessary that care should be taken that the operation is per- 
formed in such a manner that the developing permanent teeth, or their 

crypts, are not injured. In some instances 
the developing crown of a bicuspid has 
been brought away in extracting a deciduous 
molar, owing to the position of the crown 
of the former tooth between the unabsorbed 
roots of the latter. 

The Extraction of Roots of Teeth. — The 
extraction of roots is sometimes a difficult 
operation, but usually they are more easily 
removed than entire teeth, especially when 
they have remained in the alveoli for a con- 
siderable time after the loss of their crowns, 
and have not become exceedingly fragile 
from decay. When long retained, the at- 
tachment of roots becomes weakened by 
their loss of substance and absorption of 
their cavities, together with the deposition 
of bone at the apexes of their cavities to 
such a degree as to render their removal 
easy, as they are held in position simply by 
their connection with the gum. It often 
becomes necessary, however, to extract 
firmly implanted roots, owing to their sepa- 
ration from the crowns when attempting to 
extract the entire tooth, and great difficulty 
is often encountered, and to such a degree 
as to render it necessary to use special in- 
struments devised for these cases. The 
instruments employed for the extraction of 
roots are known as root-forceps, and eleva- 
tors, and, as a general rule, these root forceps have long and slender 
beaks, which are not adapted for the application of great force; hence 
the movements made with them should be gentle, as well as effective. 
Figs. 295, 296, and 297 represent useful forms of root-forceps. Figs. 
295 and 296 are designed by Dr. M. H. Cryer for the extraction of 
any single-rooted tooth, and for third molars, and frail lower incisors. 




Fig. 300. 



THE EXTRACTION OF TEETH. 



429 



The slender beak bayonet-shaped forceps, devised by Dr. B. F. 
Arrington, and represented by Fig. 297 is a useful instrument for 
difficult upper roots. 

Fig. 299 represents the common forms of elevators. In using the 
elevator, care is necessary that the instrument does not slip and wound 
the mouth of the patient. 

In the employment of the elevator, an adjoining tooth or root, if 
present, is used as a fulcrum; in other cases, the thumb of the hand of 
the operator holding the instrument may be thus used. The point or 
edge of the blade of the elevator is inserted between the root to be re- 
moved and the adjoining tooth or root, and by a slight rotary motion the 




Fig. 301. 



root is forced from its cavity. An instrument in the form of a screw is 
also used for the extraction of frail roots, and single-rooted teeth. 
(Fig. 300.) Before the screw is introduced into the root, the walls of 
which have become greatly funnelled out by decay, so as to render them 
incapable of sustaining the pressure of the forceps, the exposed surface 
of the root should be reamed out to remove the soft, decomposed 
matter, and thus a sufficiently firm hold for the screw be secured. The 
screw is then carefully inserted by half-turns until it obtains a firm 
hold in the root, and force in the line of the axis of the root is then 
applied, and its extraction accomplished. The screw, after it is se- 
curely fixed in the root, may be detached from its handle and the 
beaks of a forceps applied to the root, the screw within affording sup- 
port, and the frail root be successfully extracted. 



43° 



THE EXTRACTION OF TEETH. 



Gum La ticcts. — The use of the lancet, when necessary, precedes the 
application of the forceps for the purpose of separating the adherent 
gum tissue at the necks of the teeth. The form of forceps 
as at present constructed, with thin sharp-edged beaks, 
renders the use of the lancet only necessary where there 
is a risk of laceration or tearing the soft tissues sur- 
rounding the tooth or root to be extracted; in the case 
of deeply imbedded roots, and third molar teeth, and 
teeth standing alone, the gum lancet may be advanta- 
geously employed. Fig. 301 represents useful forms of 
lancets, and Fig. 302 an all-metal lancet which is capable 
of being effectually sterilized. Fig. 301 (3) represents 
a useful lancet for separating the gum tissue from the 
posterior surface of the neck of a third molar tooth. 

Fig. 301 (5) represents a useful form of lancet for 
liberating erupting deciduous teeth, opening abscesses, 
and performing other surgical operations. The manner 
0} using the gum lancet when extracting teeth is as fol- ■ 
lows: The sharp edge of the blade is pressed against 
the neck of the tooth and within the free edge of the 
gum, and passed around the inner and outer surfaces of 
the neck as deeply as possible, after which the blade of 
the instrument is inserted in the interproximal spaces 
anterior and posterior to the tooth to be extracted. By 
such a method the membranous attachment of the tooth 
at its cervical portion is completely severed, and a way 
is made for inserting the edges of the beaks of the 
forceps; the danger of the slipping of the lancet is also 
avoided by applying the edge at an angle to the neck, 
and a secure hold upon the tooth obtained with the 
forceps. When extracting the deciduous teeth, the use 
of the gum lancet is unnecessary and at the same time 
injudicious, for the reason that these teeth are less firmly 
implanted than the permanent teeth, the process about 
them being softer and more yielding, and at the period 
when their removal is necessary their roots are so much 
absorbed and their attachment to the alveolar cavity is 
so greatly weakened that but little force is required to 
detach them. The employment of the lancet in the case 
of the deciduous teeth is also injudicious, for the reason 
that the pain caused by this instrument may be such as to prevent a 



Fig. 302. 



THE EXTRACTION OF TEETH. 43 1 

further continuance of the operation without force is employed on the 
patient, which is always unpleasant and to be avoided if possible. 

The Casualties Attending Tooth- extraction. — The operator should 
at all times be prepared to avert and also to successfully meet the 
dangers attending tooth-extraction, which may be enumerated as 
follows: The fracture oj the whole or a portion of the crown of the 
tooth is the most frequent accident occurring during this operation, 
and may be occasioned by an ill-adapted instrument being used; by 
its improper application; by too much force being applied, and too 
forcible movements made in loosening the tooth. This accident may 
sometimes be unavoidable, and when such is apparent it is better to 
inform the patient of its probability. 

The extraction of the wrong tooth may occur as the result of failure 
to make a careful preliminary examination; or from an incorrect diag- 
nosis; or from carelessness in applying the forceps, especially when 
the teeth are crowded. If the conditions are favorable, replantation 
may be resorted to. 

Fracture of the alveolar process may, to a limited degree, and where 
it involves the margins of the alveoli only, be a common necessity in 
extraction, but in no case should the fracture be so extensive as to cause 
serious injury. 

Fracture of the jaws is not probable when using the forceps as at 
present constructed, without excessive and unnecessary force is em- 
ployed, or the bone is in a diseased condition. 

A sound tooth may be extracted when it is joined by a cemental 
fusion with the roots of another requiring removal, and in such a case 
may be an unavoidable accident. 

The escape of a posterior tooth or root into the larynx or pharynx 
may occur when a tooth, such as a third molar, suddenly leaves its 
cavity and escapes from the forceps during the operation of extracting 
it. If the fingers cannot remove the tooth, resort may be had to the 
pharyngeal forceps. 

Dislocation of the lower jaw is an accident only likely to occur 
from a laxity of the ligaments of the temporo-maxillary articulation, 
due to a previous luxation from any cause. 

Syncope or fainting is a common and unavoidable accident attend- 
ing tooth-extraction. In such a case the patient should be placed in a 
horizontal position by lowering the back of the chair to such a degree 
that the feet are elevated, and the blood gravitates to the brain. Stimu- 
lation by wine, whiskey or brandy, or the aromatic spirits of ammonia, 
in doses of half a dram in half a wine-glass of water, will increase 



432 THE EXTRACTION OF TEETH. 

the heart's action; rubbing and slapping the hands, or the application 
of cold water to the face and breast, may also prove effective; after 
which the patient should be kept at rest for some time. 

Shock during tooth-extraction is often confounded with syncope, 
and as far as the ordinary symptoms of this latter condition extend, 
these two are analogous and differ in degree and duration more than 
in character. In shock there is a state of prostration, a pallor of the 
whole surface, pale and bloodless lips, a loss of luster in the eyes, the 
eyeball partially concealed by the drooping upper eyelid, dilated nos- 
trils, a cold, clammy moisture often gathered in beads upon the fore- 
head, a low temperature, weakness of muscles, bewildered mind, often 
insensibility, and there may be nausea and vomiting. The aged are 
slower in recovering from the effects of shock than the young, although 
they have more power of resistance; in the young the impression is 
more easily made, but subsides sooner than in the old. The treatment 
of shock consists in placing the patient flat on the back, and the use 
of such stimulants as brandy, or aromatic spirits of ammonia, in the 
same doses as for syncope. Heat applied to the epigastrium by means 
of flannel wrung out in hot water, or the hot water rubber bag, and 
mustard plasters are beneficial. Small chips of ice swallowed whole 
will allay the nausea and vomiting. 

Forcing teeth or roots into the antrum in the endeavor to extract 
them, especially when the alveolus communicates with this cavity owing 
to absorption occasioned by the action of pus. In such a case, the 
orifice of the opening into the antrum should be enlarged, and the tooth 
or root removed with the pharyngeal forceps. 

The mutilation oj the maxillary tuberosity in extracting an upper 
molar should always be avoided, as severe hemorrhage may result 
from the rupture of the posterior dental artery, which may be difficult 
to control; also injury to the palatine branches of nerves; in some cases 
deafness has been ascribed to such an accident; also an opening into 
the antrum, as a result of the mutilation of the tuberosity. When the 
fracture of the tuberosity is slight, the parts may be pressed together by 
the thumb and finger to control the hemorrhage when it is severe, and 
the parts packed with medicated gauze, which should remain for 
several days before removal. 

Alveolar hemorrhage from the extraction oj a tooth may result 
from the condition, of the parts involved, such as the character of the 
blood, which is shown by want of coagulability; also from diseased 
walls of the vessels, and inflammation in the adjacent tissues; and 
finally from the predisposition of the patient, as in hemophilia. To 



THE EXTRACTION OF TEETH. 433 

determine whether the blood is coagulable, a small quantity may be 
caught in a vessel, and if it forms a clot in the course of two or three 
minutes much cause for alarm is removed, and the line of treatment 
sufficiently clear, as the diagnosis may indicate the cause to be either 
vascular or mechanical. A failure in the contraction of the mouths 
of the bleeding vessels, or adhesion of the vessels to the walls of the 
surrounding bony canal, or the rupture of an abnormally large vessel 
may also be causes of alveolar hemorrhage. Usually the hemorrhage 
after the extraction of teeth ceases within one hour, although a slight 
oozing may continue longer, and does not require treatment; if it 
should be more prolonged, as the result of great inflammation in the 
adjacent parts, or the patient is anemic, or predisposed to the hemor- 
rhagic diathesis (hemophilia), treatment for its arrest is required. 

For the arrest of alveolar hemorrhage (arterial), such styptics are 
useful as tannic acid, gallic acid, iodoform gauze, alum, nitrate of 
silver, perchlorid or persulphate of iron (either of which may be used 
in solution or powder) , or carbolized resin (resin and phenol in chloro- 
form), or adrenalin chlorid, or styptic-colloid (a combination of tannic 
acid, collodion, and tincture of benzoin), or orthoform. The prepara- 
tions of iron and nitrate of silver are considered objectionable on ac- 
count of the clot formed by them being soluble in the blood, and the 
escharotic action of the nitrate of silver not being limited to the alveolar 
cavity, and the surface of the wound thus extended. 

The local treatment consists in first removing the clotted blood from 
the cavity, and this is especially necessary in case of secondary hemor- 
rhage, where the clot may be found protruding from the vacant cavity, 
and in some cases almost filling the mouth. After the removal of the 
clot, the alveolar cavity should be syringed with ice-cold water, towmich 
is added a small quantity of phenol sodique (phenate of soda), and a 
pledget of cotton or lint saturated with the styptic applied to the apex 
of the cavity and over the mouth of the bleeding vessel. 

Dry absorbent cotton is then introduced over the styptic, and 
firmly condensed, so that the cavity is tightly filled to and a little be- 
yond its orifice. In severe cases of alveolar hemorrhage, a compress 
is a valuable adjunct, in order to increase the pressure on the cotton 
plug, filling the cavity. Such a compress may consist of a cork with 
a concave end to fit over the cotton plug, and of such a length as will 
permit the opposing teeth to press against it with some force; or it 
may consist of either semiplastic gutta-percha, or modeling com- 
pound; tannic acid, or other styptic, is incorporated in the gutta-percha, 
a plug of which is held by the pliers for a short time in hot water to 
2 s 



434 THE EXTRACTION OF TEETH. 

soften it, and after the bleeding cavity is dried with hot absorbent 
cotton, the warm styptic plug is firmly pressed to the bottom of the 
cavity, and held there until it hardens; also bathing the root of the 
extracted tooth, when it is a single root, with the styptic and returning 
it to its cavity; also a plug of half hardened plaster of Paris; also when 
the hemorrhage occurs from the cavities of several teeth, a plaster 
impression of the mouth, or a part of it, taken in the ordinary manner, 
and allowed to remain in position for some time before attempting 
its removal. Other mechanical styptics such as matico leaf, spider's 
web, burnt cork, puff-ball, powdered resin, etc., have been suggested. 
When matico leaf is employed, the fresh leaf" is preferable, or if in a 
dry state it may be moistened with water and then rolled into a con- 
venient form, with the rough side outward and forced into the cavity. 
Packing the cavity with cotton moistened with Canada balsam is also 
recommended, as it does not require any prolonged pressure. Car- 
bolized resin may be applied on a saturated strip of the fungus amdou. 

The plugs containing the styptic should be retained in position for 
from 24 to 48 hours and then be cautiously removed ; and if a compress 
is applied, the jaws should be secured and continuous pressure main- 
tained by a four-tailed bandage passed from the chin over the head. 
During the treatment the patient should be kept at rest, and abstain 
from the use of hot fluids, alcohol, and tobacco, as they relax the ar- 
teries, and favor a return of the hemorrhage. In connection with the 
styptic, and in cases where the hemorrhage has resulted from the ex- 
traction of a tooth or root which has been held in place only by gum 
tissue, and the cavity after extraction is of little depth wherein to pack 
the styptic, the following internal remedy has been suggested by Dr. 
W. L. Robinson, and can be administered w T ith benefit: Three grains 
of tannic acid dissolved in one- third of a tumbler of water; two tea- 
spoonsful, to be given every five minutes until three doses are taken, 
after which the same quantity is given every fifteen minutes. When 
such measures as have been referred to for the arrest of alveolar hemor- 
rhage fail, resort may be had to the cautery, either the galvano cautery, 
or the Paquelin benzoline cautery. 

The ajter-pains of extraction when due to pericementitis, or any form 
of septic infiltration, may be relieved by either filling the vacant cavity 
with a pledget of cotton soaked with phenol sodique, or with a solution 
composed of glacial carbolic acid, gj, liq. potassae, gj, and water 
5 viij ; or by applying to such a cavity one drop of a one per cent solu- 
tion of nitro-glycerin in half a wine-glass of cold water; or a five per 
cent solution of equal parts of cocain and iodoform. If such local 



THE EXTRACTION OF TEETH. 435 

applications fail, a solution of one-eighth of a grain of morphine may 
be injected into the gum over the vacant cavity. 

The after-treatment of extraction is often of great benefit to the 
patient. In ordinary cases the use of a twenty per cent solution of 
phenol sodique is of great service, or a three per cent aqueous solution 
of pyrozone, especially if the case has been one of pericementitis or 
alveolar abscess; either of these antiseptic solutions may be used as a 
mouth wash, and the mouth rinsed for several days. Filling the cavity 
with powdered orthoform, as soon as the bleeding has subsided, is also 
beneficial. Where an alveolar abscess has existed for some time 
previous to the extraction of the tooth, and the process has to a degree 
become necrosed, the cavity should be syringed with a solution of ten 
grains of either the sulphate or the iodid of zinc, which will separate 
the dead from the living portion of the bone, forming a sequestrum. 

When extracting teeth a careful observance of the rule before re- 
ferred to, namely, "that no movement should be made with the 
forceps faster than the eye can readily follow," may prevent the oc- 
currence of accidents liable to attend this operation — namely, serious 
fractures, tearing the gums, etc. Should the gum adhere so firmly to 
the process that it begins to tear away, the operation should be 
suspended until the attachment is severed by the lancet or curved 
scissors. 

Sterilizing Instruments. — The absolute sterilization of operating 
instruments, such as forceps, etc., is demanded, inasmuch as infected 
matter is much more readily communicated by them through wounds 
than by the fingers of the operator. Sterilization is so easily accom- 
plished that there is no excuse for neglecting it. A simple and effective 
method is by immersing the instruments in boiling water to which one 
or two per cent of carbonate of soda has been added to prevent rusting. 
Five minutes immersion in such a solution will answer for forceps 
and three minutes for smaller instruments, unless they have become 
coated with a thick dry coat of infectious matter, when a longer boiling 
is required, and a subsequent immersion in a one to thirty per cent, 
solution of phenol. Lysol may be substituted for the phenol as it 
will not rust the instruments, and, hence, does not require the use of a 
solution of soda. Trichlorphenol is also an efficient sterilizing agent. 

The strictest aseptic and antiseptic precautions should be ob- 
served when operating on the mouth. 

The extraction of teeth under the influence of anesthetic agents 
has become so general, and there are so few cases in which either a 
local or a general anesthetic is not admissible, that a writer on this 



436 THE EXTRACTION OF TEETH. 

subject has declared it to be an almost barbarous procedure, when 
performed without the aid of such an agent. 

The operator should, however, in all cases be governed by the 
condition of the patient, which can be determined by a physical ex- 
amination. Local anesthetic agents applied by the hypodermic 
method are employed to obviate the dangers of general anesthetics, 
which are administered by inhalation. When using the hypodermic 
method, several dangers are to be avoided: 1. The needle of the 
syringe should not penetrate a vein, as the entire dose may be carried 
to vital centers; hence, a locality should be selected for puncturing that 
is free from veins, nerves, and large blood vessels; the vascular and 
soft structures of the cheeks beyond the gum should also be avoided. 

2. Both the needle of the syringe, and the anesthetic solution, 
should be rendered sterile before using; otherwise an abscess may 
result from infection. The direct application of a strong solution 
of the anesthetic agent to be used to the area of the gum into which the 
needle is to be inserted, will enable the puncturing to be made without 
pain. 

The selection of a general anesthetic agent, when one is preferred, 
should be governed by the condition of the patient and the nature 
of the operation; and the physiological action of the agent employed 
should be well understood. 

A combination of nitrous oxid and oxygen, although transient in 
its effects, may answer for the majority of cases of tooth-extraction, 
especially when few teeth are to be removed; while in other more pro- 
longed operations, as the extraction of a number of teeth and roots, 
sulphuric ether may be preferable; or after anesthetization by nitrous 
oxid, the effects may be continued by the inhalation of ether. For 
the physiological action of the different anesthetic agents, and the 
manner of their administration, the student should consult authorities 
on this subject. Before extracting teeth under the influence of an 
anesthetic agent, the operator should be prepared to meet all dangerous 
symptoms liable to occur. Restoratives, such as aqua ammonia for 
inhalation, aromatic spirits of ammonia for internal or subcutaneous 
use, also brandy or whiskey as stimulants, together with tablets of 
sulphate of strychnine gr. ^ to ■£$ for subcutaneous use. For weak 
and debilitated patients, the subcutaneous injection of morphine, gr. 
J to J, and gr. t ^ to 2 ^-g- of atropine, previous to the inhalation, is rec- 
ommended. The heart and respiration should be carefully examined 
previous to the administration of every general anesthetic, as a wise 
precautionary measure. A suitable mouth prop or gag, for separating 



THE EXTRACTION OF TEETH. 437 

the jaws and keeping them open, is a necessary adjunct, especially 
in the use of nitrous oxid, on account of the rigidity of the muscles. 

All of the instruments necessary to be used should be within easy 
reach, and in case where a number of teeth are to be extracted, the 
number of forceps should be limited, so that there may be as little 
change of instruments as possible, and for this reason the universal 
forceps are to be preferred. 

In the administration of a general anesthetic, the operator should 
invariably insist on the presence of a third person in the room on 
account of possible hallucinations on the part of the patient. 

As soon as the tooth is removed from the mouth, the head of the 
patient should be slightly inclined, so that the blood may run into the 
cuspidor, and the patient kept at rest until complete recovery takes 
place. 

Whether teeth should be extracted when affected by pericementitis, 
or alveolar abscess, is a mooted question. With the remedies now 
employed for the relief of the after-pains of extraction, the writer can- 
not see any necessity for subjecting a patient to prolonged suffering 
by delaying the removal of the offending tooth. 



CHAPTER XXVII. 
THE PLANTING OF TEETH. 

BY C. EDMUND KELLS, JR., D. D. S. 

The planting of teeth in the human jaws may be done under 
various conditions, and therefore the operations may be classified, 
chronologically as they were introduced into the practice of dentistry, 
as follows: 

i. Replanting. 

2. Transplanting. 

3. Implanting. 

Replanting. — By this term is designated the operation of restoring 
to its original socket the tooth which has been torn therefrom either 
accidentally or intentionally. This operation has been more or less 
in vogue ever since the days of Ambrose Pare, who died in 1590, and 
today is considered good practice by many of our ablest operators, 
under the following conditions: 

A. When the tooth has been accidentally removed by force. 

B. When a tooth has been accidentally removed by the forceps. 

C. As a last resort to cure a refractory alveolar abscess. 

A. In almost any case where one or more of the anterior teeth 
were knocked out, it would be no less than criminal neglect for the 
operator not to at least attempt their replacement. Under these 
circumstances the tooth should be carefully washed and examined. 
If the crown is found fractured or badly cracked, it should be cut off 
and replaced by an artificial substitute. If carious, it should be filled. 
Pulp chamber and root canal should be cleansed and filled. The 
writer prefers to fill from the crown, using oxy-chloride of zinc for 
filling the pulp chamber and canal, after which the foramen is enlarged 
and the canal drilled and tapped, and a gold screw inserted, using 
the S. S. White "anchor" screw instruments for the purpose. This 
insures the substantial and perfect sealing of the end of the canal. 
The cavity in the crown is then filled with whatever material is best 
suited to the case in hand, after which the tooth is placed in an anti- 
septic solution. 

As to the best time to replace the tooth, there appears to be a 

439 



440 THE PLANTING OF TEETH. 

difference of opinion. Some operators prefer to await the subsidence 
of the local inflammation which naturally follows the injury, whilst 
others insist that the sooner the teeth are replanted, the better. 

However, whenever the tooth is replaced, the method of procedure 
is about the same. The entire mouth and socket should first be sprayed 
with an antiseptic solution, and the region about the socket protected 
by napkins. The hands having been previously well cleansed by the 
use of carbolic soap, the blood. clot is removed from the socket which 
is then carefully swabbed out with cotton saturated with the antiseptic 
solution. The tooth is then taken from its bath, a crystal of resorcin 
placed upon its apex and then quickly inserted into the socket. If 
by slow and gentle pressure the tooth cannot be returned to its original 
position, the writer believes it better practice to enlarge the socket 
rather than shorten the root. 

Just as a surgeon considers it necessary to hold in firm apposition 
the two ends of a broken bone, so it is essential that the replaced 
tooth should be firmly fixed in its position. While wire or silk ligatures 
are used by some, it is undoubtedly better to swage by the usual 
method a cap of No. 30 pure gold to fit the crown of the replaced tooth 
and one or more on each side, which, when cemented in place, will 
hold it firmly in position during the process of repair — usually about 
four w r eeks. This splint should not extend quite to the gum line and 
the proper occlusion of the teeth should be carefully considered. 

The after treatment of these cases consists in applying the tincture 
of aconite and iodin (equal parts) twice daily to the dried gums about 
the socket and adjoining teeth until all soreness disappears. The 
patient should be instructed to thoroughly cleanse the region about 
the replanted tooth after each meal, which can best be done with an 
antiseptic solution in an ordinary rubber bulb syringe. With this 
the liquid can be readily and forcibly injected between the teeth and 
thus keep them free from debris. 

The patient should be kept under constant surveillance and 
should the splint loosen, it should be re-cemented at once. At the 
end of the fourth week the splint should be carefully removed and if 
the tooth is not found to be perfectly solid, replaced and worn until 
perfect union has been obtained. 

B. A tooth might be accidentally removed by the forceps by the 
slipping of the instrument during the operation, due to the move- 
ment of the patient, or by the operator in undue haste placing his 
instrument upon the wrong tooth. 

Again, the crown of a lower first molar having been lost, the 



THE PLANTING OF TEETH. 441 

second molar may have tipped forward to such an extent that any 
attempt to remove the ofttimes diverging roots of the first molar would 
result in dislodging the second bicuspid. 

Such roots should be separated by a suitable instrument in the 
dental engine and each root extracted separately which would remove 
all possible danger to the second bicuspid. 

The same method of treatment previously described should be 
followed in cases of accidental extraction, and in such instances the 
teeth always replaced without unnecessary delay. 

C. Notwithstanding the advanced methods of treatment of diseased 
teeth, by amputation of the ends of the roots, removal of necrosed 
portions of the alveolar process, etc., etc., there still present, from time 
to time, cases of alveolar abscess which cannot be cured by the ordinary 
means. 

Usually these conditions are caused by either the root filling or 
a broken instrument protruding through the end of the root, or on the 
other hand from the failure of the root filling to reach the end of the 
canal. 

Under these circumstances, when all other methods have failed 
and as a last resort, the operation of replanting is justified, and usually 
results in a cure. 

Here again the operative procedure differs radically with different 
operators. Some always cut off the end of the root and do not replace 
the tooth for some time, waiting for the conditions about the socket to 
improve. Others never alter the roots if it can be avoided, and replant 
at once. The writer uses the latter method. 

In extracting a tooth for the purpose of replanting, the utmost 
care must be exercised in selecting forceps that fit the tooth and will 
not check or mar the crown. 

Once it is in hand, the cause of the trouble will be seen and must 
be removed. The tooth is then treated as previously described. 
The socket is carefully washed out, making sure to include and cleanse 
the pus pocket thoroughly, curetted if necessary, and the tooth replaced 
under antiseptic conditions and splinted firmly in place. Under these 
circumstances the splint should have been made before the tooth was 
extracted. 

Replanting for the cure of pyorrhea is practically impossible. 
The operation is not warranted when the disease is in its incipiency, 
at which time the operation might prove successful in eradicating the 
disease, and later on when it would be tolerated, the loss of the socket 
renders it impracticable. 



44^ THE PLANTING OF TEETH. 

Prognosis. — Usually, sooner or later, the roots of replanted 
teeth become absorbed and finally the teeth are lost. However, such 
teeth have been reported still in good condition twenty years after 
replanting. The writer has under observation a first lower molar 
still in good condition which he replanted over fifteen years ago. 

Fig. 303 shows model and a skiagraph of this case taken during 
the preparation of this chapter. 

These roots present a very unusual appearance for a replanted 
tooth. As will be stated later on, the pericementum shows in a 
skiagraphic picture as a white line around a normal root. In this 
instance this white line is present in its entirety, and it assuredly appears 





Fig. 303. 

that the pericementum was revivified and not obliterated as usual, 
which is most remarkable. This tooth was replanted in less than 
two hours after extraction. 

Transplanting is the operation of introducing into a fresh natural 
socket a root either freshly extracted or not. This operation also 
dates back to the days of Pare, and has always been practiced more 
or less until recent years. 

However, at this date, we may safely say it has become obsolete, 
the necessity for it having been overcome by present methods of crown 
and bridge work, and the more modern operation of implanting. 

Implanting. — By this is meant the drilling of a socket into the 
alveolar process, and implanting therein a natural root. 

In 1885 Dr. W. J. Younger, of San Francisco, conceived and per- 
formed this operation, and it was at once and without much thought 
adopted by very many operators. 

It being decidedly the most spectacular operation ever devised 
for clinics, scores of teeth were publicly implanted within the following 
year or two, and as most of these operations were performed under 



THE PLANTING OF TEETH. 443 

decidedly unfavorable conditions, failure was the almost universal 
result. These unfortunate results proved so very disastrous that the 
operation so far as the profession in general was concerned was dis- 
continued almost as abruptly as it was adopted. 

Notwithstanding these general results, here and there a careful 
operator appreciated that implanting with discretion was to a certain 
extent a success, and therefore had a field of usefulness decidedly 
its own. 

At this writing, when we know that implanted teeth have rendered 
service from five to fourteen years, it is not rational to absolutely con- 
demn the operation. 

Indications. — When a case presents with one or several of the 
eight anterior teeth missing in single spaces and the alveolar process 
is full, hard and healthy, it may be stated without fear of contradiction 
that a denture is the least desirable method of their replacement. 
A bridge is satisfactory while it lasts, but in the present stage of the 
art, such is by no means permanent work, and when it does fail it 
leaves the patient in a worse than his original condition, through the 
loss of the supporting roots. < If therefore the patient is a good healthy 
subject, implantation is certainly indicated, and if that fails, bridging 
may still be resorted to. 

Again, cases present "where the temporary lateral remains in situ 
for many years after it should have been succeeded by a permanent 
tooth. Finally the tooth is lost and a skiagraph reveals the absence 
of the permanent tooth in the alveolus. 

In these cases, the alveolar process is full and there is plenty of 
space therein for the making of a socket, and if the patient is in good 
health, certainly it would be better to at least first attempt implantation 
before mutilating the adjoining tooth by bridging. 

Precautions. — The drilling of a socket in the alveolus sounds 
like a very heroic operation, while as a matter of fact when compared 
to some others, such for example as the extraction of impacted third 
molars, it is very simple. 

As before stated, if the alveolar process is not sufficiently large 
to contain the socket, it should not be attempted. Otherwise the 
only precautions necessary are to sufficiently comprehend the 
anatomy of the parts so as to avoid entering the nasal fossa or the 
antrum, or injuring the contents of the anterior palatine canal in the 
upper jaw, or the inferior dental nerve in the lower. 

The suggestions for the antiseptic treatment given for replanting 
hold good in implanting. 



444 



THE PLANTING OF TEETH. 



It has been found that mature roots are most desirable for implant- 
ing as they appear to withstand the process of absorption more suc- 
cessfully than young teeth, and only small straight roots should be 
used. 

In drilling the socket, great care must be taken not to perforate 
either the external or internal alveolar plate, which would insure 
failure of the operation. 

Procedure. — As a natural tooth can rarely be found to suit the 
case in hand for implanting, any desirable root may be used and 
a suitable artificial crown, preferably porcelain, mounted thereon 
after the canal has been filled. An impression is first taken, and 
in the model made therefrom, a hole is drilled to represent the socket 
to be made in the jaw. In this the root is placed w T hile the crown is 
made. The complete and absolute fixation of the implanted tooth 




Fig. 304. 



being necessary, the writer considers that the gold splint as recom- 
mended for replanted teeth should be used here as well, and this can 
be made from this model after the crown is completed. 

The root and its finished crown mounted thereon is now carefully 
cleansed and placed in an antiseptic bath. 

There is nothing better than a compressed air spray for use in the 
planting of teeth, but if that is not at hand, a good atomizer should 
be used with a sterilizing bath. The mouth is thus sterilized as for 
replanting, the hands carefully cleansed, and the points of all instru- 
ments to be used immersed in a sterilizing bath. 

Small pieces of sponge, having been previously boiled, are also 
placed in the bath. 

Cocain or eucain, as preferred, is then injected so as to thoroughly 
anesthetize the territory to be operated upon, whereupon all is in 
readiness for the first step of the operation, which is 



THE PLANTING OF TEETH. 



445 



The cutting of the flap, which has been done in three ways: 
i. The ordinary X incision which leaves four small corners of the 
gum to be turned up. 

2. The letter H cut which gives the operator two small 
flaps to take care of, and 

3. The ( ) shaped cut which gives him but one. 

These are shown in Figure 304, and an instrument well 

shaped for their execution in Figure 305. 

The cuts should be clean and to the bone, and with this 
instrument the periosteum and gum are separated from the 
alveolar process and turned upwards. 

If coarse bladed round burs are to be used for drilling the 
socket, the flaps of the gum in the first and second method 
may not be much injured, but if the reamers are used they 
would undoubtedly be badly cut, it being impossible to hold 
them out of their way. 

Experience has proven that if provision is made for ample 
restoration of the gum upon the labial surface of the implanted 
tooth, the lingual surface need not be much considered. In 
fact the satisfactory restoration of the gum tissue appears to 
be about the least of the difficulties of implanting. 

If, therefore, the reamers are used the third cut should be 
made, as the flap being large and single can be held away 
from the cutter by any suitable instrument. 

Drilling of the Socket. — For this purpose the following 
instruments are listed in the dental catalogues. (Fig. 306.) 

The writer prefers the Ottolengui reamers, and proceeds as 
follows (Fig. 307) : 

A, being the tooth to be implanted, three reamers are 
selected, one of each size of the root at the points marked B 
C D. Setting the collar upon the smallest to gauge the full 
depth of the socket, the flap is held away, the parts again 
sprayed and the socket quickly drilled to this depth. The 
gauge on the second reamer is set to the point D, and the socket 
is correspondingly enlarged to this depth. This operation is 
repeated with the third reamer to the point C. We now 
have a socket which we are assured is of the required depth 
and of the shape shown in Fig. 308. 

Resuming our medium size reamer, and being careful to main- 
tain our antiseptic precautions, the steps of the cavity are gradually 
trimmed away, and we find that with few fittings of the root (after 



Fig. 305. 



440 



THE PLANTING OF TEETH. 



each of which it is returned to the antiseptic bath), we have expe- 
ditiously accomplished the making of a satisfactory socket. 

Dr. Robert Eugene Payne, of New York, has used the following: 
An old tooth brush handle is trimmed at one end to as near the shape 
and size of the root to be implanted as is possible — and it is then 
boiled in distilled water for two hours — after which it is placed in the 
sterilizing solution. When the socket is nearly finished, this "form" 
is pushed in with considerable force and the alveolar process being 
more or less yielding is crowded away and the root will fit the socket 



snugly 



o oooO 



# # $ 




Fig. 306. 



The socket is then well sprayed, and carefully swabbed out with 
prepared pieces of sponge that no debris be allowed to remain therein. 
A few crystals of resorcin are placed upon the apex of the root, when 
it is pressed into place and splinted firmly into position, where it must 
be held from four to ten weeks, as may be necessary. 

The same after treatment as described for replanting should be 
followed here. Strange as it may appear, but little after trouble 
need be expected. 

Difficulties to be Met. — The problem of holding the implanted 
tooth firmly in place is often a difficult one. Likewise is it often 
impossible to mount the crown in such alignment upon the root as 
to have it exactly correct when placed in position in the jaw, this 



THE PLANTING OF TEETH. 



447 




Fig. 307. Fig. 308. 



being due to the socket in the mouth not corresponding exactly with 
the one made in the plaster cast. 

To overcome these the writer has fitted the coping and post to 
the root and set it with gutta-percha as shown in Fig. 309, and im- 
planted this only. A clasp band is then fitted to the adjoining teeth with 
a projecting arm and tube, the latter fitting the post exactly. In Fig. 310 
is shown such method as it appears in the mouth. By this means is 
avoided the thickness of the gold splint upon the 
occlusal surfaces of the teeth, and the opportunity 
for maintaining aseptic conditions about the im- 
planted root is the best. 

After the root has become firm, the post is 
readily heated and removed, when the porcelain 
crown can be added and a perfectly satisfactory 
alignment of the same be obtained. 

By means of the Roentgen Ray the condi- 
tions about the roots of planted teeth may be 
studied with great satisfaction. In Fig. 311 at 
A is shown a skiagraph of a replanted tooth, 

and its normal neighbors are seen at B. B. The pericementum is 
more or less clearly shown around the latter, while it has been 
obliterated about the planted tooth, the distinct outlines of its root 
having faded away. 

This clearly proves the accepted theory of the attachment of 
planted teeth, which is as follows: The root of the planted tooth 
becomes attacked and absorbed at different points, which 
places are immediately filled in with a deposit of bone. 
Thus a solid union is formed between the cementum and 
the socket, the pericementum becoming obliterated. 

Implanted teeth may be detected in the mouth by 
tapping their crowns lightly with a steel instrument, the 
resultant sound being very different from that given off 
by a normal tooth the root of which is surrounded by 
pericementum. 

The duration of the root evidently depends upon the relative 
ratio of damage and repair. In some cases, the absorption proceeds 
exceedingly slowly, in others much more rapidly; but the day finally 
comes when the attachment becomes too weak to support the crown 
and it is exfoliated like a temporary tooth. In Figure 312 is shown 
the remains of an implanted tooth which had stood in the mouth but 
little over a year. 




Fig. 309. 



448 



THE PLANTING OF TEETH. 



Figure 313 is a skiagraph of an implanted root, the crown from 
which had come off. This is a splended illustration of the causes at 
work around such roots. The lines surrounding the cuspid and 
central roots upon either side, represent the pericementum. This 
is absent about the implanted root, it having been obliterated by the 
process of anchylosis which has taken place. Near its apex can be 
seen the first stages of the process of absorption. 




Fig. 310. 

In Fig. 314 is shown a skiagraph of a replanted tooth nearing its last 
days of usefulness. The gold screw with which its apical foramen 
had been sealed is plainly shown. Notwithstanding the extensive 
absorption, this tooth is still quite solid and gives no external evidence 
of its early fate. 

Many implanted teeth have lasted from three to six years, while 






Fig. 311. 



Fig. 312. 



Fig. 313. 



a few have been reported from ten to fourteen years. The majority, 
however, fail within two years and some secure no attachment what- 
ever. 

The writer considers that implanted teeth which prove of service 
for five years should be classed amongst the successful and satisfactory 
dental operations. 



THE PLANTING OF TEETH. 



449 




Fig. 314. 



Artificial Roots. — Immediately upon the discovery of the loss 
of implanted teeth by absorption various operators experimented 
with artificial roots of numerous materials and shapes. Posts, screws, 
and cribs of silver, tin, gold, platinum, lead and porcelain; all these, 
and probably others were tried but all 
proved failures. Dr. R. E. Payne con- 
ceived the idea of drilling a perfectly 
circular socket and enlarging it at the 
bottom. In this was placed a closely 
fitting cylindrical capsule which was 
then rilled with soft rubber which upon 
pressure expanded the capsule and 
rendered it solid at once. An ordinary 
continuous gum tooth was then cemented 
in the capsule as shown in Figure 315. 

Eut unfortunately the tissues of the jaw will not tolerate these 
capsules and they remain in place but a few weeks. One might 
suppose that if a silver elbow-joint could be successfully inserted 
in an arm and made to do good service, and 
silver nails remain in bones in which they have 
been driven, that a silver capsule carefully ex- 
panded in the jaw would also remain in place, 
but such does not follow, the reason being that 
the structure of the long bones is different from 
that of the alveolar process. 
Fig. 316. T n Figure 316 is shown a platinum capsule 

which was expanded in the jaw, by an instru- 
ment devised for the purpose, where it remained but a few weeks. 

In Figure 317 is shown a skiagraph of another of the forms of cap- 
sules implanted by the writer, the picture having been taken shortly 
after the operation. This was held in place by 
a clamp and tube for three weeks, when this 
retaining appliance was removed and the cap- 
sule appeared perfectly solid. However, about 
six weeks later it loosened and came out. 

Sterilizing Agents. — Mercury bichloride, 1 
to 1000, forms a good bath for all purposes in 
connection with these operations. However, 
natural crowns should not remain in it indefinitely, or they may become 
discolored. 

Hydronapthol dissolved in hot distilled water to the point of 
29 




Fig. 311 



1 



Fig. 317. 



450 THE PLANTING OF TEETH. 

saturation and then filtered, forms an excellent spray for the mouth 
as well as a bath for the instruments and roots. 

Conclusions. — Before writing this chapter a circular letter w r as 
sent to many prominent dentists of this and other countries. From 
the replies thereto, the w r riter is lead to the following conclusions: 

Replanting is practiced by many conscientious operators of this 
day. 

Transplanting is not practiced at all. 

Implanting is still practiced by some operators, who, like the 
writer, believe that under certain circumstances it is advisable. 



CHAPTER XXVIII: 
PYORRHEA ALVEOLARIS. 

BY JOHN DEANS PATTERSON, D. D. S. 

The work of writing upon the subject of ''Pyorrhea Alveolaris" 
in a way to enable the dental practitioner to more successfully cope 
with that most distressing and destructive condition surrounding 
the dental organs becomes difficult only on account of the fact that 
members of the dental profession have so often been led to believe 
by a majority of the writers upon the subject that the disease is the 
expression of systemic conditions, and that until those conditions 
are corrected the treatment is well-nigh hopeless. 

The operator who is a student of disease, if he gives credence to 
these statements is also well aware of the fact that the diseases of 
faulty metabolism, or those resulting in faulty metabolism — which, 
according to these writers, are largely causative of the condition known 
as "pyorrhea alveolaris" — are diseases rarely cured or even greatly 
modified; and we can then readily see that logically the operator hesi- 
tates to undertake a task which promises so little success to the 
operator or benefit to the patient. 

At the outset of this brief consideration of the subject the author 
desires to state, with a confidence based upon observation and expe- 
rience for over twenty-five years, that the condition or disease commonly 
known as "pyorrhea alveolaris" is amenable to treatment, effecting a 
cure as readily and satisfactorily as the other lesions of the dental organs, 
whether the systemic conditions which affect the progress of the disease 
are present or absent. The writer is not alone in this belief, as many 
careful observers and practitioners have proved in their clinical ex- 
perience the correctness of the statement. 

No sane member of the dental profession can rely upon cures in any 
or every dental pathological condition with an absolute precision, nor 
can he promise that when a cure is brought about it will be permanent, 
for always a disease will again be reproduced when like conditions en- 
viron which produced the original lesion; but the chances for relief 
to the sufferer are as promising and as positive in pyorrhea alveolaris 
as the relief and cure following the process of filling a majority of ca- 
rious teeth. 

45i 



452 PYORRHEA ALVEOLARIS. 

The prime object of this writing is to disabuse the mind of the 
dental operator of a belief in the incurability of the condition in ques- 
tion, and to teach that he should avail himself of all the ways and 
means to do this work,. just as he does for the best methods of filling, 
crown- and bridge-work, inlay-work, or any other of the usual operative 
procedures, or he will not do his duty to suffering human beings. 

GENERAL REMARKS UPON THE NATURE OF PYORRHEA 
ALVEOLARIS; ITS ETIOLOGY AND PATHOLOGY. 

Upon the best of authority it may be stated that the susceptibility of 
tissues to the attack of irritants of whatever nature varies greatly in 
different individuals; and that tissue character is largely of heredity. 
This is markedly observed in the oral mucous membrane. It is well 
known that a slight irritant in a given case produces distressing in- 
flammation, and that in another case with the same amount of irritation 
the mucous membrane is not in the least prejudiced. A small point of 
calcic deposit which encroaches upon the gingival border at the cervix 
of a tooth will in one case produce pain and inflammation, and in 
another, larger amounts of calculus are scarcely appreciable to the pa- 
tient. 

In the last edition of Stengel's work upon "Pathology" this pre- 
disposition of tissue to irritation is commented upon as follows: 

"The normal system is able to cope with the determining causes 
of disease to a certain point by its general vitality and regulative func- 
tions. " "The degree of resistance to irritation differs in different in- 
dividuals in different races, or with people living in varying climatic 
conditions. In some the degree of resistance may be so great that 
certain diseases are never contracted. In other persons there is a 
recognizable weakness of resistance in one direction or another, which 
constitutes a definite predisposition. The latter may be either heredi- 
tary or acquired. By hereditary predisposition is designated abnor- 
mal weakness of resistance transmitted from father or mother to off- 
spring. They predispose to a number of allied affections. This is 
striking in the case of neuropathic heredity, in which various forms 
of nervous disease may appear alternately or irregularly in members of 
a family. In the occurrence of hemophilia we have another notable 
example." 

The disease under consideration is observed by all careful clinicians 
to often affect each member of a family and their offspring, and the 
explanation must be found in the character of tissue which exhibits a 
weakness of resistance and which is handed down from one generation 



REMARKS UPON THE NATURE OF PYORRHEA ALVEOLARIS. 453 

to another. It cannot be held, however, that this difference is always 
due to heredity, although it may be safely said this is generally true; 
for the tissue is brought to a weak condition at times, which has been 
acquired. General debility from ill health and a starved condition of tis- 
sues from lack of nutritive supply frequently prejudice to the attack of 
irritants. It is quite doubtful, however, that the acquired predisposing 
conditions, which require usually a long period for the establishment 
of prejudiced tissue, is more than a minor factor in the causation of 
pyorrhea. 

The mucous surfaces are ever under suspicion of certain char- 
acteristic inflammations and ulcerations, but it can scarcely be said 
that diseases like pyorrhea alveolaris have their inception without local 
irritation, whatever the predisposing factors may be. 

For nearly half a century the most advanced pathologists have 
granted that even tumors no doubt have a local cause. Whatever 
the predisposition found in heredity or environment, yet without local 
irritation of some description the proliferation of cells found in hy- 
pertrophy does not ensue. If investigators in pathology tell us this, 
well may we put at once aside the claim often made, that the condition 
under consideration is per se of constitutional origin or caused by a 
specific micro-organism. Those who seek for the etiology of pyorrhea 
in obsure forces should return to the plain and provable logic of cause 
and effect, and forsake the speculative and unreliable. In the etiology 
of the condition the following statement may be safely. made: Any 
irritant, of whatever nature, which impairs the integrity and continuity 
of the gingival gum margin, may cause pyorrhea; and without this 
impairment the condition will not be established. This may be followed 
by another proposition; viz., Systemic conditions or a constitutional 
diathesis without local irritation do not destroy the integrity of the 
gingival border. 

The irritation which may dissolve the integrity of the gingival 
border may be presented in various forms. The deposition of the 
calcareous salts from the saliva upon the necks of the teeth is the usual 
form of irritation; next in importance may be classed the nests of putre- 
faction and fermentation about the gingival border and interproximal 
spaces; again, mouth-breathing dries the delicate border, and thus 
function is interfered with; and in all these irritations we have the pro- 
tective reaction of inflammation against a common enemy — irritation. 
Other irritations may also be mentioned, and include most prominently, 
banded crowns, careless use of ligatures, the use of wedges, the presence of 
cavities holding food matter and which is wedged in the process of masti- 



454 PYORRHEA ALVEOLARIS. 

cation into the interproximal spaces; also careless operative procedures. 
It is the firm opinion of the writer, however, that calcic deposits from 
the salivary secretions combined with food detritus, the nests of fermen- 
tation and putrefaction, the changes caused in the mucous membranes 
by mouth-breathing, the unnatural cervical tooth surface formed by 
banded crowns, and proximal decay, must be considered the primal 
and usual causes of interference with and destruction of the relation 
of the gingival margin of the gum with the cervix of the tooth. The 
lesion of the gingival border is a result of continued {generally long-con- 
tinued and persistent) irritation, such as is found under conditions above 
stated; and the factor of causation found in wedging, ligaturing, and 
other temporary interference with the gingival border consequent on 
operative procedures, can scarcely be cited as active causes for the es- 
tablishment of pyorrhea alveolaris. In summing up the positive and 
possible causative factors in producing this disease, the writer's close 
observation of hundreds of cases confirms the statement that less than 
five per cent have other origin than that found in irritation from calcic 
deposits from the mouth-fluids combined with decomposing food re- 
mains. 

When the first stages of the disease are established by a solution of 
the integrity of the gingival border from any one of the causes stated, 
the disease will progress, slowly or with rapid steps, until the tooth is 
eventually lost. The rapidity of the course of the disease will depend 
upon the amount of local irritation and the predisposition present ; but 
without hygienic care, remedial measures, or surgical interference, it 
remains in the majority of cases but a question of time when the tooth 
investment will be entirely lost and the affected organ exfoliated. 

Let us now trace more minutely the pathology involved from the 
first untoward symptoms. 

With the initial lesion and the inflammation of the gingival border 
there is at once established the condition found in all inflamed territory 
— viz., the exudation of the contents of the nutritive vehicles, which 
with the presence of micro-organisms eventually introduces the breaking 
up of the exuded vessel contents and the adjacent tissue into pus. 
There rarely is found an exudation w T hich does not soon exhibit sup- 
purative processes. This condition in which exudates and pus are 
exhibited gives rise to the precipitation of the calcic matter which is 
invariably present in all exudations, and is deposited wherever a con- 
venient bursa for its reception is afforded. The explanation of the 
source of the serumal or sanguinary points and plaques found in py- 
orrhea is the simple and reasonable one, that in all inflammatory con- 



REMARKS UPON THE NATURE OF PYORRHEA ALVEOLARIS. 455 

ditions there are exudations, and whether they are simple serum, as in 
the first stages, or pus, as in the later suppurative stages, there is in 
this matter calcium phosphate, calcium carbonate and magnesium 
phosphate, and in the changed environment caused by functional dis- 
turbance these salts are logically precipitated, and thus form an irritant 
to the tissue about which it is deposited, inciting by its impact or touch, 
inflammation of soft tissue and absorption of bony tissue until the tooth 
organ is exfoliated. In the opinion of the writer, the serumal deposits 
in pyorrhea are subsequent to the initial inflammation, and are 
directly from the inflammatory products. 

In 1889, in a paper read before the joint meeting of the Amer- 
ican and Southern Dental Associations at Louisville, Kentucky, the 
writer made the claim as stated above, and in substantiation spoke 
as follows (p. 172-173, Transactions of the American Dental Asso- 
ciation, published 1889) : 

"Now, as a matter of fact, all prominent pathologists agree that 
accretions of calcic matter may make their appearance as a deposit 
from purulent matter from inflamed territory in any part of the human 
body. Upon this subject I desire to quote from the Hand Book of 
Medical Sciences, Vol. I, p. 743, as follows: 'Calcification consists in 
the abnormal deposit of earthy matter in or around the elements of a 
tissue, or in the morbid product of a pre-existing inflammatory process.' 
' The circulation of the blood may be retarded and thus favor the pre- 
cipitation of the calcareous matter which it normally holds in solution.' 
' Calcification rarely, if ever, depends solely upon general causes. 
There is always a local influence — very often it is due to a pre-existing 
inflammation. Old accumulations of pus, extravasations and exuda- 
tions are exceedingly prone to calcification.' 'The simplest mode of 
explanation is as follows: A certain amount of calcareous matter is a 
normal constituent of the blood, in which it is held in solution by the 
carbonic acid always present in sufficient quantity to keep in solution 
twice the normal amount of earthy matter. When the circulation is 
impeded, the carbonic acid, because of its great diffusibility, is readily 
absorbed by the tissues, or goes to form new compounds, necessitat- 
ing a precipitation of the calcareous matter. This is likely to occur 
in all tissues of the body. ' " 

After quoting the foregoing high authority, the writer said : " With 
these facts before us, does the presence of calcic deposits in the pockets 
of pyorrhea alveolaris still surprise us, and must we yet indulge in vague 
surmises over its origin?" What I said at that time is a firm convic- 
tion today. These deposits are from purulent matter and are the con- 



456 PYORRHEA ALVEOLARIS. 

sequence of irritation and inflammation from the various local causes 
referred to. They are not precedent to a lesion, but invariably are 
subsequent to irritation and exudation. 

The inflammatory process established with the precipitation of 
serumal calculus from inflammatory products, the continuation of 
the disease goes on to the breaking down of tissue as before mentioned, 
from the impact or touch — the mechanical irritation; and this force is 
supplemented by the presence of pyogenic bacteria, which in their 
life processes cause toxins, purulency, suppuration, which by gravi- 
tation and capillary attraction, infect and destroy the tooth invest- 
ment. Soon there is noticed at certain points pockets of increased 
depth, and they indicate their presence upon the gum by a reddish or 
purple line. Now the tooth often commences to change its position. 
It elongates, protrudes, or rotates — drawn by the remaining normal 
attachments, or by the protective reaction of tissues which seek to 
rid the economy of a diseased member. This looseness, and the con- 
sequent malocclusion, is also an irritant factor. These conditions soon 
cause a profuse formation of pus from about the diseased teeth, which 
exudes about the teeth, and in deep constricted pockets the pus at 
times finds its way through the tissue at the lower point of the pocket 
and the abscessed condition points as in ordinary alveolar abscess. 

When the disease reaches the apical territory, the nutritive ves- 
sels to the pulp frequently are deprived of their function, and the pulp 
takes on a pathological condition w T hich results in its death; and so is 
added the additional irritation of common alveolar abscess. If the 
condition of pyorrhea is of long continuance, the root of the tooth in 
some cases is found to be attacked and absorbed in spots at the focus 
of inflammation. This has been noticed without the complication of 
the death of the pulp, though more frequently when the disorganized 
pulp tissue assists in the irritation. The giant cells often present in 
continued inflammatory territory in their strenuous attempt to protect 
tissues are found to destroy them. In pyorrhea the root of the tooth 
is occasionally observed indented in this manner immediately beyond 
the subgingival territory. 

The above related conditions continuing unalleviated, the entire 
attachment of the tooth becomes diseased and obliterated and the 
organ is exfoliated. 

In this brief description of the etiology and pathology of pyorrhea 
the writer has made no attempt to differentiate the various aspects 
found in the condition which are noticed, and which, in his opinion, 
need not be classed as distinct conditions simply because the degree of 



THE TREATMENT. 457 

irritation and the degree of predisposition are different in the different 
cases and produce various degrees of destructiveness. A "true pyor- 
rhea" and one that is not true is a distinction to the writer not warranted. 
Because in one patient the predisposition of poorly nourished tissue is 
present and an apparent ( ! ) absence of local irritation, there is no 
reason why the condition should receive some specific name, when com- 
pared to a perfectly normal patient whose teeth are exfoliated by a 
disease whose pathology is similar. There can be no objection to 
denominating pyorrhea alveolaris "simple" or "complex," and when 
that is done, let us be content to observe its various phases exhibited 
when observed in patients who have various diatheses influencing 
its rapidity or destructiveness; but let us eliminate a so-called dis- 
tinctive nomenclature for the various phases of this disease, unless 
it demonstrates a better scientific title to such distinction than is as yet 
made plain. 

THE TREATMENT. 

Referring to the etiology of caries of the teeth, the late Dr. W. H. 
Atkinson once said to the writer: "We all have our differences of 
opinion as to the cause of tooth decay, but one thing remains true: 
that if we absolutely knew the cause, it isn't likely we could fill teeth 
a bit better." This leads me to remark that it is very fortunate that 
while writers and speakers seem far apart upon the etiology of pyorrhea 
alveolaris, there is a great unanimity of opinion as to the treatment. 
Upon this we are upon comparatively safe ground, and upon consulting 
all, we find that whether the disease is considered systemic or local, 
hereditary or acquired, from degeneracy or faulty metabolism, syphilis 
or scrofula, catarrh or calomel, mouth-breathing or micro-organisms, 
ligatures or lithemia, indolence or insanity, wedges or whisky — the 
treatment is the same. Those who name the condition "interstitial 
gingivitis," "alveolar ulitis, " "phagedenic pericementitis," "calcic 
pericementitis," "pyalogenic pericementitis," "hematogenic peri- 
cementitis," "infectious alveolitis," " odontolithus, " etc., etc., agree 
almost literally in treatment with those who call the conditon "Riggs' 
disease," or "pyorrhea alveolaris." There is a growing conviction 
among all that with the removal of all irritating and infectious 
matter from and about the teeth, and the maintenance of a vigorous 
oral asepsis, pyorrhea alveolaris, if not too far advanced, is curable. 

DIAGNOSIS. 

To the inexperienced, rules by which a correct diagnosis may be 
reached, thus framing a ground for remedial treatment which will 



458 PYORRHEA ALVEOLARIS. 

promise a cure, are well-nigh impossible; but it can be safely stated 
that if a tooth has lost three-fourths of its normal attachment, or ex- 
hibits a looseness indicating that nothing remains save a fibrous or 
ligamentous attachment, the loss of the tooth is usually inevitable and 
extraction is advised. It has been proved, however, that where it is 
practicable to place a permanent retainer upon such tooth or teeth, 
attaching them to those comparatively firm, freeing them from depos- 
its, sometimes changing their position in order to stimulate repair of 
investment, and maintaining scrupulous hygienic conditions, even 
these ordinarily hopeless cases are given long life, and the patient is 
freed from the necessity of bridge work or plates. This must, how- 
ever, be said: that the loss of teeth is far better than the continuance 
of those in the economy from which a pathological condition producing 
infection of good tissue cannot be divorced. Too many practitioners 
in the treatment of the dental organs, whether for pyorrhea or other 
morbid conditions of tooth roots, lay too great stress upon the evils 
resulting from a broken denture from extraction; even if substitution 
is possible, they subject patients to discomfort and infection, often 
to an alarming extent, because of their horror of sacrificing a tooth, 
pretending to argue that mastication, digestion, and nutrition are there- 
by so interfered with that they choose the lesser of two evils. It must be 
patent to those of experience and observation that more than one-half 
of the human family manage very cleverly to exist, and in robust health, 
w T ith a very limited masticatory apparatus. With a few bicuspids 
and molars more time is required for sufficient mastication than if the 
full complement of teeth is present; but it is nevertheless true that 
with care, a very few pounds pressure, and more time, the ordinary 
foods can be most properly prepared for deglutition. It is very com- 
fortable to have teeth like a rhinoceros to champ and gnash with a 
pressure of hundreds of pounds; but the average citizen is not a dock- 
hand who must consume his meals in a few minutes, and if his choice 
grinders cannot be made comfortable or sanitary by the best skill, then 
let them be as " the eye that offends. " 

When the diagnosis is completed and the hopeless teeth and roots 
are out of the way, the next step is the eradication of disease causes and 
disease results by surgical procedure; the all-important step, without 
which no amount of systemic treatment or no amount of local therapeu- 
tics will avail to cure or much alleviate the condition. 

Preparatory to establishing the surgical work the operator should 
first obtain a complete history of each case. First as to heredity; find 
if there is a history in progenitors of loose teeth and loss of teeth with- 



DIAGNOSIS. 459 

out caries; find how long the condition has existed, the character of the 
discomfort, whether there has been annoyance from bleeding gums, 
swelling, or a foul taste or odor. Enquire as to possible acquired pre- 
disposition and as to what remedial measures or operative procedures 
have previously been instituted. Examine carefully with delicate 
explorers, mouth-mirror, and electric mouth-lamp all affected sur- 
faces as to depth of the disease galleries and as to looseness of the 
teeth. 

At this point the next question is to determine if the pulps should 
be removed from any of the affected teeth upon which operations are 
to be performed. Some years ago it was quite a popular belief that 
these affected teeth were in better condition for future usefulness 
minus the pulps. It was argued that after pulp removal the nutritive 
supply formerly going to the pulp was switched to the pericementum; 
so thousands of pulps were sacrificed needlessly and harmfully. Care- 
ful observers afterward came to the conclusion that in the treatment of 
pyorrhea a more rapid and more perfect cure was brought about when 
the pulp remained, and that the assertion of more nutrition and strength 
to the tooth's investment when pulp removal was practiced was with- 
out scientific basis. It is, however, true that there are two situations in 
which the pulp should be obliterated before further operative proced- 
ures are instituted : first, in case the diagnosis convinces that the pulp is 
in a pathological condition; and second, to afford anchorage for a per- 
manently adjusted splint for retention. If in the progress of the disease 
the solution of the integrity of tissue at the apical territory has been 
accomplished, it may safely be said that the pulp is probably affected, its 
usefulness past, and it should at once be removed. Again, the irritation 
causing the pulp to be in a state of chronic irritation may be occasioned 
by the exposed condition at the cervix of the tooth or below it, on 
account of gum recession introducing thermal shocks. If this condi- 
tion is present, the pulp should also be removed. In the second class of 
cases, the removal of the pulp in order to properly adjust an appliance 
to retain loose teeth, the operation should be, as in the former case, 
prior to the scaling operation, as upon the surface of the root from 
which the pulp has been removed the operation of scaling for obvious 
reasons is less painful. 

There is yet another operation which frequently may be prop- 
erly performed before proceeding further, and that is the making and 
cementing to place the retainer to be worn. This will guard against 
starting the tooth from its socket in forcing deposits away, and also 
prevent movement of the root causing pain. 



4t)0 PYORRHEA ALVEOLARIS. 

RETAINERS. 

The operator's ingenuity will show him which of the great num- 
ber of retaining appliances will serve best in a particular case. Many 
of the splints or retainers used in orthodontia serve admirably. The 
purpose of the splint or retainer is to prevent discomfort from move- 
ment, to obtain complete surgical rest, without which the formation 
of repair tissue is prevented. 

Now commences the preparation of the mouth by the removal 
of all micro-organisms and fermentative or putrefactive matter by 
irrigation. First this should be done by the patient with warm water, 
followed by water at an increased temperature-, up to 140 F. This 
should be followed by DobelPs solution, which is superior in removing 
remaining viscid fluids found in the mouth. Now the operator will 
follow with vigorous use of the syringe of strong force with 
blunt point, and following with a slim point which will enter the 
deep pockets and flush out all inflammatory products which are mov- 
able. After all possible poisonous micro-organisms and infectious 
detritus have been removed, the next step is to obtund the tissues to be 
operated upon, so that the operation may be rendered as painless as 
may be possible. The injection of the tissue is not advised. 

OBTUNDENTS. 

For the purpose of obtunding, many preparations have been ad- 
vocated and many methods advised. It is not our purpose to canvass 
all of them, on account of necessary brevity, but only to advise, after 
repeated trial, what seems most effective for the purpose. When the 
field of operation has been selected, dry the parts and pockets and 
saturate with the following mixture, for which we are indebted to Dr. 
Cravens, of Indianapolis: 

"Put half an ounce of chloroform in a suitable bottle, add freshly 
pulverized hydrochlorate of cocain, shaking and waiting a few seconds 
after each addition of the akaloid until the solution clears. To this 
add six to eight drops each of oil of cloves, cassia, and menthol, and 
add to all a flavoring extract to render agreeable." 

This mixture seems greatly more effective in obtunding the tissue 
than all other cocaine solutions used by the writer, and when placed 
upon a pledget of cotton and pressed into the interproximal space 
gently at first and then with force, the relief from the pain of removing 
the serumal deposits is marked. It may here be said that the strongest 
solutions of cocain may be used in the mouth for various purposes 
without danger of unpleasant results if the patient is instructed not to 



RETAINERS. 



46l 




Fig. 318. 



Fig. 319. 



Fig. 320. 






Fig. 321. 



Fig. 322. 



Fig. 323. 



JT^ 





Fig. 324. 



Fig. 325. 
Description of Retainers. 



Fig. 326. 



Fig. 318 illustrates the commonly adopted method of retaining in a fixed position the 

lower incisors. 
Fig. 319 shows a splint retainer. 

Figs. 320, 321, 322, illustrate the retention of the superior six anterior teeth. Fig. 320 
the teeth devitalized and prepared to receive a strong post, Fig. 321 shows the 
retainer before adjustment. Fig. 322 the appliance cemented to place and completed. 
Fig. 323 shows a method of retention for posterior teeth. Pulps usually removed and 
channels cut in the occlusal surfaces for a strong brace, the appliance is most satis- 
factory when ihe channel is filled as an inlay. 
Figs. 324, 325, 326 illustrate the authors original device for retention of loose lower 
incisors. Fig. 324 is the skeleton. Fig. 325 the lingual aspect after completion. 
Fig. 326 the labial aspect after completion. 
The description and making of this retainer is as follows: — 

Ligate the teeth firmly in the proper position. In cases of Pyorrhea very often the 
position of the teeth is changed, but they can be ligated and placed in the position desired. 
The next step is with the proper drills, a No. 1 round bur followed by No. 2, make a hole 
through the upper portion of the tooth, within about an eighth of an inch from the incisal 
edge which will accommodate 21-gauge gold wire. When these cases present we know 
very well the horn of the pulp has receded, so that there is little danger from encroach- 
ment upon the pulp. The next step is to take an impression with red base plate gutta- 
percha of the lingual aspect of the teeth, surround this impression and pour upon it the 
low fusing metal, which can be done in a very few minutes. In this way a very good 
model will be obtained. Swage upon that a piece of 22-karat gold plate 36 gauge, place 
it in the mouth, and indicate with an instument through the holes where the pins should 
be. Punch the holes, place the wire and solder upon the lingual side. Then put it in 
the mouth and arrange it and burnish gold to fit exact. Use pure gold if desired. Re- 
move this very carefully without changing its position. Then reinforce with solder the 
lingual side until sufficient strength is gained. Before putting it on finally, grind or file 
the plate to the proper shape and polish, and when it is finally completed, place the 
rubber dam upon the teeth and cement it in place. 

After the cement is thoroughly hardened, cut off the pins and rivet them with a round 
smooth burnisher in the engine, dress off the extra cement and the operation is completed. 
There is no other appliance ff r the retention of the lower front teeth that is so delight- 
ful and permanent and that is so readily cleansed. All the gold that shows is the end of 
the 21 gauge gold wire, which cannot be seen by any one standing two or three feet from 
the patient. 



40 2 PYORRHEA ALVEOLARIS. 

swallow one drop of saliva, but to eject every particle of mouth fluids. 
The mixture is also forced into the pockets with the delicate-pointed 
syringe, and thus penetrates deeper than when introduced with a 
broach wound with a shred of cotton. 

Dr. Austin James, of Chicago, recommends a method of further 
rendering the use of scaling instruments less painful, by polishing all 
portions of the diseased root with various forms of wood points used in 
a porte-polisher and charged with pumice and phenol sodique, and 
burnishing w T ith suitable forms of burnishers. A test of this method 
by the writer has given most excellent results. Before this polishing, 
if there are large plaques of salivary concretions', of course they should 
be dislodged. Dr. James also advises that only this polishing be done 
at the first sitting, and that in a day or two the sensitiveness will be 
less than if the instrumentation immediately followed the polishing. 

SURGICAL TREATMENT. 

Now T comes the instrumentation, and it may at once be said that the 
instrument wmich will accomplish the w^ork of removing all deposits 
and irritant matter from the root, leave it smooth so that repair tissue 
will form about it, and do this with the least mutilation of the soft tissue, 
is the instrument to be advised. In all operations involving the gingi- 
val tissue it is extremely important that the rope-like border surround- 
ing the cervix of the tooth be not severed or mutilated, on account of 
the fact that with serious lesion it recovers slowly and is seldom re- 
produced like the original. So the instruments must be of a form, 
strength, delicacy and effectiveness not perhaps demanded for any 
other operation in dental surgery. 

Until in recent years, the instruments used and advised have been 
chiefly those doing their work w T ith a pushing motion. In 1886 Dr. 
G. V. Black, in the "American System of Dentistry," wTote as follows: 
" The instruments for this operation should for the most part be formed 
to work with a pushing motion. Curved and hooked instruments 
formed to work toward the hand with a pulling motion may be of 
service in removing the bulk of the larger concretions of salivary cal- 
culus, but they are of inferior value in the removal of the last portions 
of the deposits or for serumal deposits high up under the gum. For 
this purpose all hook instruments, no matter how delicately formed 
should be discarded, and slender points made to work with a pushing 
motion substituted." 

The advice of Dr. Black, in the experience of all who sought to 



SURGICAL TREATMENT. 463 

treat pyorrhea was deemed good; and while various instruments with a 
draw motion were formulated, they were found generally to be inade- 
quate, and the push instrument first prominently brought to notice by 
the late Geo. H. Cushing with his admirable and delicate set of six 
scalers, and other sets with modifications of the Cushing forms, have 
been the reliance of nearly all who operated for pyorrhea. But the 
instrument with a pushing motion has had its day. Even the stoic 
cried out against it. It was the despair of those treating the disease 
with the push instrument to daily hear: "Well, my teeth can go; I'll 
never stand that pain again." Notwithstanding this, many patients, 
appreciating the beneficent results, would return and submit to the 
subsequent minor operations often necessary to control the 
situation. In the meantime those who appreciated and demanded 
more humane instruments, upon the principle of placing a point be- 
yond the deposits or other irritant matter and displacing it with a draw- 
ing motion, were continually advising and devising less painful methods, 
and with the result that more perfect results with less pain can be se- 
cured with properly formed hook instruments. 

The dental operator has many times in the past expressed opinions 
denying the possibility of bettering methods and instruments, but sub- 
sequently they have been so improved as to bear little resemblance to 
what was once considered all that could be desired. The clumsy and 
impracticable instruments used by Dr. Riggs, which operators at that 
time thought were well-nigh perfect for the cure of pyorrhea, are now 
nowhere used save for removal of larger crusts of salivary calculus, and 
it seems to us an astonishing thing that Dr. Riggs secured such a meas- 
ure of success with them without first entirely dissecting away the soft 
and underlying tissues surrounding the root of a tooth. So now we 
find that the vaunted push instrument must give place to the more per- 
fectly constructed draw instrument, which avoids pain and which 
leaves the surface of the root in a much smoother condition, insuring 
better repair of tissue. 

The description and illustration of instruments for the treatment of 
pyorrhea alveolaris which have been evolved by various inventors, and 
which have led to more or less of success in removing irritant matter 
from the roots of teeth and brought a measure of success to the origina- 
tors and those who have placed reliance upon them, is not the purpose 
of this presentation; but it is the purpose to present in the following 
illustrations forms of instruments deemed greatly superior in effective- 
ness to any heretofore offered, their use causing less pain, and of such 
shapes that all surfaces of affected teeth can be scaled and smoothed, 



464 



PYORRHEA ALVEOLARIS. 



/r\ /r\ 



A 



i4->\ 




l\ 



/^x 



A~\ <L\ 



rC-A 



IUI 



fC- 



Li 



V7 Yf 



i 



H 



Fig. 327. 



SURGICAL TREATMENT. 



465 




IX 





Ja 



i\ 



Fig. 327. 



30 



4OO PYORRHEA ALVEOLARIS. 

which, in the opinion of the writer, cannot be accomplished with in- 
struments heretofore commonly used for the purpose. 

The principle upon which these instruments are planned can only 
be imperfectly described, but may be outlined as follows: The work- 
ing point is a delicate yet strong hook, designed to be thrust beyond 
the plaques of calcic matter, which are drawn towards the crown of the 
tooth, thus dislodging and removing the irritant. Each instrument 
is so formed that a short distance from the hook the blade rests upon 
the root, and thus guides and steadies the working point, and also pre- 
vents undue furrowing of the root. The hook is rounded upon all 
corners and surfaces save upon the immediate "or cutting edge, so as 
not to tear or lacerate the soft tissues. The great variety of forms 
allow the operator to follow the tooth contour with a minimum of pres- 
sure upon the inflamed tissue. Thus, the extreme apical territory can 
be reached and operated upon, if desired, with an entrance between 
the gum margin and the root of not more than a thirty-second of an 
inch, which is the usual distance from the working point to the back of 
the hook. These instruments have little spring, the great variety of 
shapes precludes that necessity, and the rigidity enables the operator 
to use great force, which is often essential in removing deposits which 
have long existed. The working point is constantly on line with the 
handle of each instrument; thus turning or slipping is prevented, and 
greater precision without undue force is attained. These instruments 
have but recently been placed upon the market. The inventor is 
Dr. C. M. Carr. 

The illustrations show some of the primal forms. In the full 
set each primal form has a number of variant angles and curves, 
with which different but allied contours of each root and cervix can 
be reached most perfectly and without unnecessary wounding of tis- 
sues. In beginning the operation of scaling, it is w T ise to select only 
that number of teeth for one operation which can be entirely finished 
at the sitting. If the disease is in the incipient stages, frequently a 
number of teeth can be treated; if the condition is in the advanced 
stages, from one to four should be the limit. In all cases each opera- 
tion should be limited to an hour, for, in the first place, whatever the 
means used for obtunding, the operation is more or less painful; the 
teeth operated upon are also left in a condition acutely sensitive to 
thermal changes, and if many teeth are treated at one siting, the dis- 
comfort is distressing for many days on this account, so it is surely 
best to confine this discomfort and the painful scaling to a limited time 
and a limited area to prevent accumulated discomfort in cervical terri- 



MEDICATION. 467 

tory on account of thermal irritation, and to prevent shock from the 
unavoidable pain of the operation. With the correct diagnosis as to 
the extent of the disease and the selection of the suitable instruments, 
there must be a determination upon the part of the operator that the 
roots selected to be operated upon at any sitting shall be entirely freed 
from irritating deposits and the surfaces left in a condition to en- 
courage the new tissue of repair to form. The surgical part is not com- 
plete upon the removal of deposits, but after that these surfaces should 
be smoothed and polished as perfectly as may be. About the crowns 
and the cervix of the tooth engine instruments with brushes, strips, 
rubber cones, etc., of a great variety of shapes, are applicable; 
beyond the gum margin hand instruments must be used. The 
various wood and other points, held in a suitable porte-polisher 
and charged with an abrasive, must reach all possible surfaces. 
Experience has taught that the time spent in smoothing the 
roots is well worth the endeavor, for the rapidity and permanency of 
the recovery is greatly enhanced, and the operation cannot be con- 
sidered completed until as much time is given to the polishing as to 
the removal of deposits. 

The polishing concluded, then comes the removal of all loosened 
detritus with the hot water used in a strong force syringe with slender 
special points which will reach well down into the pockets; these points 
are best made of silver or German silver, and can be fashioned by any 
instrument-maker. 

MEDICATION. 

The Pharmacopeia has been searched for the drugs which will 
best assist to a cure. Each operator has a favorite remedy among 
the germicides, antiseptics, or stimulants. Some form of an acid 
has strong supporters; those usually relied upon are sulphuric acid in 
the form of the aromatic, and lactic acid. There can be little doubt 
of the efficacy of the acid treatment for the removal of broken-down 
tissue and the stimulation of involved alveolar processes, but there 
is a very grave objection to the use of the acids, on account of the fact 
that the exposed necks of teeth are thereby rendered more sensitive to 
thermal shocks. The surfaces from which the coating of deposit is 
removed in any event are a source of great discomfort to the patient in 
whatever manner they may be treated, and as the acid treatment seems 
to greatly increase this tenderness, the writer has abandoned its use 
and substituted a 10 per cent solution of silver nitrate, which, as is well 
known, renders those surfaces much less painful. Indeed, in very 



468 PYORRHEA ALVEOLARIS. 

depraved eonditions and pockets of this disease, when the discolora- 
tion is not an objection, a saturated solution of the silver nitrate brings 
results not secured with other drugs. The 10 per cent solution is just 
short of the discoloring strength. In using the silver solution the parts 
should be protected from saliva for a few seconds. After this treat- 
ment all inflamed and diseased gum tissue should be bathed with drugs 
or combinations of drugs which stimulate absorption, act as counter- 
irritants and obtund irritated surfaces. 

This completes the surgical treatment, and if the different pro- 
ceedings described have been faithfully performed, the cure to be 
in time established now rests largely with the patient. This is an 
all-important consideration, for it is patent to all that the disease will 
recur if conditions permitting the original trouble are not entirely 
corrected. Each patient must be thoroughly imbued with the plain state- 
ment that however faithfully the surgical operation has been, there can be 
little hope of more than transient relief unless there is a determination that 
the mouth must continually be kept in a sanitary state. Observation 




Fig. 328. 

has taught us how hopeless often is the task of changing habits which 
are ingrained during a lifetime and betoken a lack of physical clean- 
liness. Patients suffering from pyorrhea must be taught by positive 
and sometimes abrupt but earnest words, that when they declare their 
mouths receive the most scrupulous care, they are simply deceiving 
themselves, and that the supposed care must be doubled and trebled 
ere a hygienic mouth condition will be present. They must especially 
be warned that the mouth must be cleansed of food detritus after each 
meal, and that once during twenty-four hours brushing with unlimited 
use of a powder for three minutes must faithfully be performed. The 
usual and universal swishing and dabbing for a few seconds upon 
only the buccal surfaces must be shown to be well-nigh useless, and 
that especially the lingual and interproximal surfaces are the points 
most needing friction. The position of holding the brush and the 
cleansing movements can best be shown upon the actual teeth in a 
skeleton or dummy. The brush recommended is one in which the 
tufts of bristles stand well apart, admitting their reaching between 
the teeth, and is illustrated in Fig. 328. After the brushing, show 



SUBSEQUENT TREATMENT. 469 

in the mouth how the gums should be massaged with the finger 
and thumb, firmly pressing the receded gum toward the cervix, thus 
pressing foreign matter out of pockets and coaxing it to its original 
anatomical position. Finally, direct that nothing is equal to the cleans- 
ing and exercise and scouring in mastication of fibrinous foods, and that 
the more sensitive the gums are the more the teeth need their natural 
use. * There is scarcely a dental arch affected with pyorrhea where one- 
half of the arch does not exhibit great difference in the disease progress, 
and it will be found that the worst condition is invariably upon the 
side not used or little used in mastication. This neglect of universal 
use comes of habit, but more often because of a defective arch or ten- 
derness in teeth or gums. Patients must be instructed that safety lies in 
the use of all teeth, and the operator must see to it that he has rendered 
that possible not only in correcting the gum disease, but in making 
faulty arches as perfect as may be possible. The frequent use of an 
antiseptic mouth wash for rinsing the mouth, and to be forced into 
the interproximal spaces with a blunt-pointed strong force syringe, must 
also be instituted. A trial of the syringe for home treatment will soon 
convince any observant operator that therein he has a great help toward 
a cure. It will be found that after the most vigorous rinsing and brush- 
ing, food particles and matter in the imperfect interproximal spaces are 
dislodged with the syringe which were undisturbed with the brush. 
Especially is the syringe to be used until repair tissue fills the pockets 
of disease with new material. 

SUBSEQUENT TREATMENT. 

If the operation has been well done, it is inadvisable to disturb the 
pockets, which are soon filled with the plasma out of which repair 
comes. The very common practice of frequent probing and medicat- 
ing is strongly condemned. Give Nature an opportunity to do the 
mending, and do not stab the protoplasm thrown from the nutritive 
vessels with medicine or touch. In sixty or ninety days examination 
should be made, and if any point of calcic deposit has escaped the initial 
operation, its position will be easily indicated by an inflamed tissue. 
This examination will also determine as to the degree of care being 
given by the patient. If it is found to be very lax, prove it so by asking 
the patient to take the hand glass, and with a suitable instrument remove 
the cheesy putrefactive matter, which can only remain under careless 
brushing. Then comes your opportunity for a lecture containing 
few words, but they will be emphatic in explaining the uselessness of 
any possible surgical operation unless followed by directions originally 



470 PYORRHEA ALVEOLARIS. 

given. Sometimes we find those instructions entirely forgotten and 
their repetition asked. On the other hand, do we find that great care 
has manifestly been observed, never fail to give warm compliment. 

SYSTEMIC TREATMENT, 

When pyorrhea is accompanied with any predisposition, whether 
hereditary or acquired, which lends to the virulence of the disease, 
such systemic treatment for the correction of the predisposition as 
found advisable should always be relegated to the patient's medical 
adviser. It is a breach of ethics if the doctor of dental surgery invades 
the general field of medicinal treatment by the' administration of in- 
ternal remedies for the correction of faulty metabolism or systemic 
conditions from whatever cause. 



CHAPTER XXIX. 
. EROSION. 

BY GEO. W. COOK, D. D. S. 

The word erosion is taken from the Latin erodere, which means 
to gnaw away. Under some conditions the term is applied to ulcera- 
tion. In geological parlance the word is synonymous with denuda- 
tion. The term is frequently used in pathological conditions of plants; 
as, for instance, if an insect has stung or poisoned a plant, causing a 
loss of substance to a particular locality, the diseased part becomes per- 
fectly smooth on its surface; this process is also called erosion. The 
word is likewise occasionally applied to certain conditions of the mu- 
cous surfaces of tissue where it is aphthous. In some of the ancient med- 
ical writings aphtha and erosion were commonly used as meaning one 
and the same thing; but at the present time the connotation of these 
two terms applies to different conditions. The term erosion, as ap- 
plied to the teeth, is usually looked upon today as a process whereby 
certain surfaces of the teeth gradually disintegrate, leaving a perfectly 
smooth expanse. However, it must be remembered that when these 
surfaces disintegrate, that is, when they occlude with the opposing 
teeth, it is not considered erosion but abrasion. 

Dental erosion, as it is understood at the present time, is for the 
most part confined to certain surfaces of the teeth in which only the 
mucous surfaces of certain soft tissue come into direct contact with the 
tooth substance. However, it has been observed that this pathological 
process sometimes appears on tooth substances where the surface of a 
tooth does not come in contact with the soft tissue. Hutchinson, of 
England, applied the term to certain conditions where the incisal edge 
of a tooth showed marked imperfections in the form of a semilunar 
appearance; a tooth in which these conditions are found we speak 
of as the Hutchinson tooth. But this in the stricter sense of the term 
is not erosion. Dr. G. V. Black, of Chicago, associates this class of 
condition and many other forms of congenital imperfections of the 
teeth with atrophy; but in no sense are erosion and atrophy alike. 

As we have just stated, dental erosion is now used to mean a grad- 
ual wasting away of tooth substance, leaving the surfaces of teeth 
as if they had been carefully polished. The condition may be present 

47i 



47- 1 EROSION. 

on only one tooth, or on a large number of teeth, sometimes involving 
practically the entire set of teeth. Sometimes it appears as if a fine 
rat -tail file had been the instrument used to make these notches or 
grooves. The condition more commonly appears in the anterior teeth. 
The labial surface of cuspids, laterals and central incisors are the ones 
that are most commonly involved in this process. It may attack the 
lingual surface of the bicuspids and molars along the gingival border, 
but this is by no means as common as on the buccal surface. My 
attention was called to a case in the infirmary, in which the surface of 
almost every tooth in the mouth was involved. I think, however, that 
such cases are very rare in comparison with those of the more common 
attacks, which, as I have already stated, usually take place in the six 
anterior upper and lower teeth. In another case there was a notched 
or grooved appearance on the lingual surface of a lower lateral incisor, 
extending diagonally across its lingual surface; the groove starting 
on the mesial and extending diagonally from the upper third of the 
incisal edge to almost a point of the juncture of the enamel with the 
cementum, and in the deeper portion extending well into the dentin 
of the tooth. 

The tooth surface that becomes involved in this affection is ordinar- 
ily situated where there is friction, which is made by the tooth-brush 
or some other like means of cleansing the teeth. It hiight also be said 
that erosion appears in individuals who have never known the use of 
a tooth-brush, or who cleanse their teeth by any other means such as 
by chewing food. I have in mind two cases in which there was ex- 
tended involvement in the ten anterior teeth of the upper jaws, the 
individuals claiming that they had never used a tooth-brush, or any 
other means by which it may be said that friction could play a part in 
the conditions of these cases. 

So far as the writer has been able to find out, John Hunter, of 
England, in his natural history of "Human Teeth," is the first to give 
a description of this affection. Since that time a number of authors 
have contributed many hypotheses for this pathological process, and 
each has tried to explain the reasons for believing that such and such 
factors are the real cause of this affection. Hunter's original idea was 
that the disease was inherent in the tooth substance itself, and that 
the disease appeared later in life because of certain circumstances, 
but these circumstances he did not account for. 

Bell, who was among the early writers upon this subject, held 
that this process was a mechanical one. This author's principal 
reason was based upon the circular deposits of the enamel substance. 



EROSION. 473 

Garretson considered the difficulty to be due to an impression, such as 
that from inheritance, upon the individual at the time of the formation 
of the enamel, in which it left a predisposition in the tooth substance 
to the formation of the future lesion. Fox laid considerable stress 
upon the fact that the affection was due to the friction of the lip, assisted 
by the saliva. Harris and Taft place the cause as due to an acid 
condition of the buccal mucus. Nuhn explained that erosion on 
the cutting edge of the front teeth was caused by an acid mucus ex- 
creted from certain glands in the tip of the tongue. Weal's observa- 
tion was that this affection never occurred on the lingual surface of 
teeth, and that the trouble must be sought on the buccal and labial 
surfaces. His explanation of this was that the folds of the mucous 
membrane of the dental arch gradually become narrower, and terminate 
with a ridge of connective tissue which is attached to the necks of the 
bicuspid and molar teeth, a condition which may extend along the facial 
surface of the gums of the lower jaw. 

In the Dental Cosmos, 1873, Dr. Charles Koch gave a descriptive 
explanation of the difference between mechanical abrasion, caries, 
and erosion of teeth. He believed that because erosion could not be 
produced artificially or mechanically, just as it appeared in the mouth, 
that the pathological process was a congenital or acquired predisposi- 
tion aided or abated by chemical reagents, or perhaps by mechanical 
means. In this particular there seems to be some confusion as to 
just what the author did mean. 

Baum believes that where the dentin of the tooth is not covered 
by gum tissue or enamel, this exposed surface of dentin exfoliates and 
mechanically falls out of its position, and by the friction of the lips and 
brush the surface of the tooth becomes polished. In 1880, W. Finley 
Thompson made an extensive study of the difference between caries 
and erosion, and wrote a very interesting paper on this subject at that 
time. He says, " caries of the teeth may attack apparently strong tooth 
structure and semi-decalcify the dentin of the tooth, which will retain 
with great tenacity its connections with the normal tooth tissue, but 
erosion seems fated to complete disorganization and this continues 
until considerable surface of the tooth is destroyed, leaving a polished 
surface." 

Dr. Edwin T. Darby expressed his opinion that the general affec- 
tion known as erosion was produced by an acid in the buccal mucosa, 
which was intimately associated with rheumatic and gouty conditions. 
C. Edmund Kells expresses the belief that it is due to an acid excreted 
by the mucous glands on the labial and buccal sides of the teeth. 



474 EROSION. 

Fairbanks, of England, laid stress on the fact that erosion of the teeth 
was due to the decomposition of undigested food in the stomach, and 
usually appeared in mouths that were exceptionally clean. Stockton 
held the opinion that erosion of the teeth was due to certain gouty 
conditions which produced a general acidity, and that an alkaline tooth 
powder arrested the progress of the disease. Bailey laid considerable 
stress on the mechanical action of the fluids of the mouth. He says: 
"In the first place, all cases of erosion are in a position subject to the 
action of the oral fluid currents, which take varying directions in dif- 
ferent mouths and even in the same mouth." He further says: " We 
know that a running stream can easily be changed, and in this way we 
are liable to have the mechanical friction produced by the current of 
flow of the fluids of the mouth." 

Billetter, of Zurich, also holds to the mechanical theory. W. H. 
Trueman believes that it is due to chemo-vital causes and that the ex- 
creting of the fluid is necessarily a chemical process. The idea that 
this destructive agent must be an acid having affinity for the lime salts 
of the teeth has but little tradition to support it. The little cap which 
we frequently see, mainly of enamel, and all that remains of a baby 
molar, is sufficient evidence that there may be, and is, formed in the 
oral cavity a true solvent of tooth tissue. This effect has been pro- 
duced by a normal physiological process. He farther suggests the 
stomachic digestion as being parallel to erosion and excludes "chem- 
ism" as being only a minor agent. Prof. James Truman considers 
the process of erosion and abrasion as extremely simple; he says that 
they are governed by the law of chemical action and that erosion is 
unquestionably the result of a chemical solution. 

Dr. G. V. Black, in the American System of Dental Surgery, 
published the results of some experiments in using the dilute solution 
of hydrochloric acid 1-400. He recorded in one experiment how T he 
took two fresh, healthy bicuspids and covered the greater portions of 
them, roots and all, w T ith gutta-percha, exposing only the crown. 
These were then placed in a jar containing diluted hydrochloric acid, 
the teeth being arranged in such a way that the current would im- 
pinge upon the outer surface of one tooth with greater force than upon 
the other. This resulted in the disappearance of the cusps and the 
formation of the groove between the teeth. The groove was more 
marked upon the one receiving the greater force of the current. A 
large number of other observations were carried out and it was found 
that the strong solutions produced general softening of the teeth, 
while a solution of 1 of acid in 5000 of water had no appreciable effect 



erosion. 475 

after three months. Dr. Black, however, did not try this experiment 
with any other substance than hydrochloric acid. I tried to duplicate 
Dr. Black's experiments but did not get the marked effect that I had 
expected. I took a U-shaped tube that was somewhat similar to the 
tube used in the apparatus designed by Kohlrausch. In this tube 
was placed a perfectly sound tooth, of which all but a small portion 
was covered with wax. Various solutions of acids and neutral salts 
were placed in this tube and an electrical current was passed through 
these solutions at alternate intervals. It was found that all the neutral 
salts, with but one or two exceptions, did not produce any disintegra- 
tion of tooth substance. But all of the acids, even though they were 
in the most diluted form, did produce disintegration of the tooth sub- 
stance when a mild current was passed through the solution. There 
are so many points of physical chemistry that enter into this process 
that it would be quite out of place to detail them here. But we might 
say this, that the conductivity of saliva differs in different individuals, 
and that those suffering from dental caries have a saliva with a high 
conductivity, which shows that there might be some of true strong acids 
present; while in the simpler form, or we might say in the mild forms 
of erosion, the saliva has a low conductivity, showing that there is some 
difference in either the acids or basic salts in the colloids in the 
saliva. The organic acids affect teeth very differently when an elec- 
tric current is passed through the solution from the way the mineral 
acids (monobasic acid) affect them. 

The above observations, to a certain degree, help to substantiate 
the electrical theory. In other words, in the saliva of mouths, whether 
or not we have acids, we have many of the electrolytic salts which ex- 
ist there not as salts so much but as associated ions. This means that 
an atom of sodium, potassium, magnesium, etc., is charged with elec- 
tricity. Therefore, they are in constant motion in the solution, it 
matters not how apparently quiet the solution may be. The substance 
in the saliva containing the negative ions is constantly passing and 
combining with the ions of a positive nature. Consequently all the 
fluids of the body that contain electrolytic salts are constantly 
producing molecular activity of the solution. Thus, in the acids, 
atoms that make up the acid groups in the saliva have a very low 
activity. 

Tomes was of the opinion that the true and only cause of the diffi- 
culty was a mechanical one. Schlenker, Walkoff, Scheff, Bastyr and 
Brandt have all expressed their opinions that the disease is the result 
of a chemo-mechanical process. They have placed stress on the 



4J0 EROSIOX. 

chemical side of the question, thus suggesting that its one cause is a 
thin layer of decalcification of tooth substance, which is removed by 
the cleansing process. 

Miller's recent investigation seems to indicate, from his view- 
point, that the mechanical action of substances such as tooth powders, 
or any agents that will produce friction, is the main factor in causing 
the wearing away of the surfaces of teeth. From all the observations, 
with but few exceptions, it seems to me that this is true. However, 
there are physical and chemical properties of saliva that, beyond any 
question of doubt, must play some role in this obscure process. I 
have in only a few instances been able to produce the eroded surface 
exactly as it appears in the mouth. I have produced erosion of teeth 
with practically all of the tooth powders and mouth washes that are 
today on the market, but in the vast majority of instances it does not 
appear identical with the cases found in the human mouth. I have 
in mind a patient suffering from erosion, in whom the care of the 
mouth has been practically neglected, so far as brushing the teeth is 
concerned. She tells me that she was trained from childhood up not 
to scrub her teeth, but to wash them with a smooth, soft cloth, and to 
do so once or twice a week only. The rest of the time the mouth 
had no care except a rinsing with water. She has well-defined eroded 
surfaces on the cuspids, lateral and central incisors, and more recently 
on the bicuspids. This case, with similar observations, would hardly 
justify us laying much stress upon the mechanical cause of erosion 
of tooth surfaces. I think the majority of observations that have 
been recorded are to the effect that the diverted activity of the mucous 
glands is the principal cause of the disease. This is the most preva- 
lent opinion held by the majority of writers upon the subject; and 
beyond any question of doubt in my mind, it is to an explanation of 
this nature that we are to look for the best light on this pathological 
lesion. 

W. X. Sudduth brought forth the hypothesis that this affection 
was due to a lowered nervous condition which resulted in a salivary 
acid. There may be an element of truth in this statement. According 
to the investigation of Halliburton most all tissue contains a mucoid- 
like substance; and according to Morner there is to be found in such 
tissues a chondromucoid, which has the composition of the following 
elements: C. 47.30, H. 6.42, N. 12.58, S. 2.42, O. 31.28. When 
this is extracted from the tissues it has an acid reaction and becomes 
insoluble in water. If it were possible to take living tissue, the activity 
of which is largely confined to excreting a mucoid-like substance, 



erosion. 477 

we should find that this tissue goes through certain chemical reactions 
in which hydrogen plays an important part. 

There are a number of acid molecules which appear in the chem- 
ical manipulation of that group of acids belonging to glycuronic acid. 
Galactose is also present in mucoid substances, occurring for most 
part among the hexoses. When split apart the latter will yield dextrin 
and furfurol, which can be oxidized into mucic acid. In the Dental 
Review, May, 1906, was published a brief article entitled, "The Role 
Played by Certain Acid Derivatives of Lactose in Erosion of Teeth." 
At that time I was strongly of the opinion that mucic acid would dis- 
solve tooth substance with perhaps a degree of success. But an in- 
teresting fact developed that this acid was easily and rapidly broken 
up by certain bacteria, and especially by those that are constant in- 
habitants of the oral cavity. Thus it was found that mucic acid had 
to be kept under aseptic conditions when acting on the tooth sub- 
stance, otherwise it became quickly broken up, forming alkali that 
did not affect the tooth. It was also found that the teeth had to be 
kept in fresh solutions of the reagent, for as soon as it had acted for a 
few hours on a tooth it extracted enough of the neutral salts out of the 
tooth substance to neutralize the mucic acid solution. I have also 
noted a vast difference in the teeth to be acted upon by the mucic acid 
as well as many other agents, and that some teeth are far more easily 
acted upon by an agent than others. 

As I have stated before, experimentally I can produce erosion with 
a large number of agents, but I have never yet been able to produce 
any but what were atypical, rather than typical, by anything except 
mucic acid. 

However, it will be remembered that galactose is not always one 
of the derivatives of the hydrolytic splitting. In the article above men- 
tioned, it was shown that the saliva might contain relatively large 
quantities of mucoid substance, containing the precursor of mucic 
acid; and by hydrolytic oxidation these substances would easily give 
rise to mucic acid. For instance, in such conditions as pregnancy, 
and various other constitutional changes in which these agents are 
present, this combined material might under favorable circumstances 
produce what is usually designated as acidosis and hyperacid secre- 
tions of the mouth, which might furnish a mucin easily oxidized into 
the various agents above mentioned. I am now more convinced of 
the possibility of such changes being so produced than I was at the 
time the article, referred to, was published. 

I followed experiments on animals by bathing the mucous surfaces 



478 EROSION. 

for a considerable time, using many times friction with various agents. 
It was observed that many of the substances that we use for the pur- 
pose of producing disinfection of the oral cavity, when used at inter- 
vals for some time on the mucous surface, produced degeneration of 
the tissue cells. The tissue, removed and stained by me, immediately 
gave an acid reaction. The micro-chemical process is one which at 
the present time is looked upon as one of the valuable means of deter- 
mining the alkalinity or acidity of the tissue elements. It would be 
quite out of place here to give the methods used in this connection. 
Suffice it to say that any one who is interested in this phase of the 
subject is referred to the work of Cross and Bevan. 

According to the investigation carried out by Acree and Hinkins, 
they found that acid saliva containing sufficient amount of acid to pro- 
duce erosion or wasting away of tooth substance may flow directly 
from the salivary glands. In nearly all of the works on physiology 
we are told that the saliva may be neutral or alkaline under ordinary 
circumstances; but, according to the investigations of the authors 
just mentioned, acid saliva is more common than we are ordinarily 
led to believe. It is not only possible for the mucous membrane to 
have an acid reaction given off from it; but it is also possible for the 
saliva, taken directly from the salivary glands, to contain acid in suffi- 
cient quantity to give a reaction. Many times the acidity of the saliva 
taken from the salivary glands contained as much acid as was found 
in the oral cavity where it had been under the influence of bacterial 
changes. 

All of this goes to show conclusively that the body substance, under 
ordinary circumstances, and that certain organs and tissues, are spe- 
cially subjected to certain physiological changes that bring about an 
acid condition of the cells and tissues, as well as of the organs irom 
which the secretion is taken. 

The investigations by McGuigan and myself have clearly demon- 
strated to my mind that we seldom, if ever, have lactic acid present in 
the oral cavity. With all of the tests we could make, by electrical 
conductivity and by optical determination, in which we polarized the 
saliva that was acid, we did not find an optically active, lactic acid. 
From these and other tests we are led to believe that the acid saliva 
of individuals affected by erosion, and of many suffering from dental 
caries, does not contain lactic acid. However, I might say that we did 
take the scrapings from decayed teeth and placed them on a micro- 
scopic slide and found, with the additionof metallic zinc, that had been 
previously prepared for this purpose, that there were crystals formed 



TREATMENT OF EROSION. 479 

that gave the appearance of lactate of zinc crystals. But our work 
on this particular phase did not give very satisfactory explanation as 
to the kind of the acid. 

There were so many isomers of lactic acid formed and these dif- 
fered so materially from the molecule formation, one from the other, 
that it was extremely difficult to say whether or not we had a lactic 
acid or some other organic acid present. We found many crystals 
that assumed practically the shape of the zinc lactate crystals. I 
think a careful review of the work of Hinkins and Acree will show that 
the crystals formed under such circumstances are very unreliable. 
Owing to the lack of space we cannot discuss this phase of the subject 
at this time; suffice it to say, however, that our opinion up to the pres- 
ent time is that lactic acid does not play any role in the cause of ero- 
sion of teeth. We are, however, of the opinion that an acid is present 
in all of these conditions, but that in the majority of instances friction 
must be applied in order that the dissolution of the surface of these 
teeth will assume a smooth, glassy-like appearance. 

Monobasic acids never give a typical eroded surface. The acids 
that come the nearest to giving a typical erosion are those organic 
acids that contain the largest number of the hydroxyl group. 

If we review with care these theories which I have quoted, it will 
be observed that all these theories deal with but one or perhaps two 
factors. The work I have done leads me to but one conclusion, and 
that is we have dealt with this problem in an elementary way. It 
should be remembered that all vital processes are of a complex chem- 
ical nature, and that erosion of teeth is a physico-chemical change of 
a greater complexity than most of those that have been suggested up to 
the present time. I can, as has already been stated, produce erosion 
with almost anything, even with water and a stick, but it is not typical 
under the microscope. Therefore we cannot say but what erosion of 
tooth substance is a complex process and not a simple one, in the sense 
that most writers have placed this subject. 

TREATMENT OF EROSION. 

The treatment of erosion is for the most part mechanical, and in- 
volves the cutting out of the eroded surface and the filling it in the 
ordinary way. One of the great advances made in dentistry is that 
of the application of porcelain in just this class of cases. However, 
I have met with considerable success in using certain agents in the 
treatment of this affection, and my greatest success has principally 
been in the use of nitrate of silver, especially in the first stages of this 



4S0 EROSION. 

process. In the early use of this agent I thought its effects were pro- 
duced by its action on the eroded surface of the tooth, but later I ob- 
served that its benefits were principally due to the action that it had 
on the mucous secretions in the location where the treatment was ap- 
plied. In other words, when the treatment was applied to the eroded 
surface of a tooth, it would necessarily come in contact with the mucous 
glands, and in this way change the secretions of these glands; so that 
whatever chemical agent was acting upon the tooth surface was in 
some way or other destroyed. 

Dr. D. M. Cattell called my attention to a case in his practice in 
which I advised the use of nitrate of silver, *as a painting over the 
mucous surface which came in contact with the eroded portion of the 
tooth. He followed this treatment at intervals for six months or a year, 
and he tells me that the erosion has practically subsided. The care 
of the patient's mouth has been just the same as it had been previous 
to the treatment with nitrate of silver. This, with a number of other 
cases, demonstrates to my mind that we have to look to the mucous 
surface more or less for the stoppage of this process. 

There are certain forms of tooth degeneration that are not strictly, 
in all respects, like that of erosion. Sensitive cavities appear at the 
gingival margin, so sensitive many times that it is quite impossible to 
touch them. This class of cases sometimes can be successfully treated 
with the application of a saturated solution of caustic alkalies like 
sodium and potassium hydrate. After two or three applications of 
this saturated solution, from one to three days apart, take a dull 
engine bur and run it over these surfaces at a rapid speed, which will 
lessen the sensitiveness of the cavity. If such applications do not 
suffice to relieve or arrest this process, then a saturated solution of 
silver nitrate should be applied. When the discoloration from the 
silver nitrate has fully formed, which always gives an unsightly ap- 
pearance, an application of tincture of iodine to the discolored tooth 
tissue, followed by ammonia, will usually remove all the stain. In the 
application of nitrate of silver to eroded surfaces, regardless of where 
these surfaces may appear, I use a saturated solution. I then remove 
the stain, in the manner above described, or by polishing; the former 
being much better than the latter. 

In writing this article I have tried to weigh with care the theories 
and ideas heretofore held by different authors regarding the cause of 
erosion. I have only quoted from those who seem to give the most 
reasonable hypotheses on the subject. I have arranged the subject 
matter, as near as possible so that the readers might analyze the sub- 



TREATMENT OF EROSION. 481 

ject for themselves, and possibly aid them in a more careful observa- 
tion of the cases that come under their care. Time and space do not 
permit me to quote all of the writers upon the subject as I should like. 
Suffice it to say that much of the material that has been written is 
very hard to analyze and secure the exact interpretation of the authors' 
ideas and just what was being formulated. 



31 



CHAPTER XXX. 
THE MANAGEMENT OF AN OFFICE PRACTICE. 

BY ELLISON HILLYER, D. D. S. 

When college and state board requirements have been fulfilled 
the graduate student faces the problem of applying the result of his 
preparatory training to its ultimate object — the practice of his pro- 
fession. 

Two paths open before him; either he may enlist as the assistant 
of another practitioner with the aim of acquiring by close contact that 
experience which only the atmosphere and surroundings of an office 
can give; or, he may elect to begin at once his career upon his own ac- 
count, relying upon his college training as sufficient. In either case it 
is but a beginning and each should feel that nothing but an assiduous 
devotion to the highest ideals and constant pursuit of further knowl- 
edge can lead to any measure of success. 

By the time a student has received his degree and license to prac- 
tice he should have learned to regard his profession as among the most 
dignified and worthy of all he can give to it. If a student regards it as 
but "a means to an end" he should press the question further and ask 
himself "what is the end?" 

He has probably heard it said many times that he will hardly grow 
wealthy by the practice of dentistry alone; if wealth is what he seeks, 
then let him choose some other path. The status of the profession 
was never elevated by one of its members seeking affluence through its 
channels but it has been raised to its present high position by the self- 
sacrifice of those who have given more to it than it to them. 
- . 'Embued with this spirit and settled in conviction as to just what 
"success" really means, let each go forth prepared to do all in his 
power for those who will come into his care; let him remember that he 
has been trained to serve and that it is his place to give the best that is 
in him with no thought of the public as existing for his benefit. 

Were this spirit to animate all our graduates the quackery which is 
the bane of our profession, as it is of all professions, would cease to exist. 
The beginner argues that "he must make his living" and proceeds to 
make it by whatever means present. This is short sighted as no great 

483 



484 THE MANAGEMENT OF AN OFFICE PRACTICE. 

success, in the highest sense, was ever achieved by lightning strides but 
by slow consistent proceeding. Thus only can a man hold his place as 
a professional man. If he prefers to prostitute his ideals and make of 
his profession a "business," with fillings and dentures at so much per 
filling and denture — that "so much" being usually as much as he can 
make the patient pay — he must be satisfied to take his place outside 
the professional pale and realize he has none but himself to blame. 

In the locating of his prospective office the student has to consider 
several things; surroundings, ease of access, availability of space and 
arrangement of reception and operating rooms. Of the first two noth- 
ing need here be said; of the latter much might be noted. 

For the best results three rooms are needed; the reception room, 
operative office and prosthetic laboratory. To the first may well be 
added a retiring room fitted with various toilet requisites. The recep- 
tion room should be made as attractive as possible. The general atmos- 
phere should be one of refinement and good taste with everything to 
detract from the unpleasant side of a visit. Good literature, maga- 
zines and books should be at hand to occupy any spare moments of a 
waiting patient. Attractive fittings and interesting pictures should be 
provided to catch the eye and by suggestion take the attention of the 
patient away from himself. Have some one — preferably a lady — in 
attendance, as much more ease is given to both patient and operator 
by the judicious services of a competent lady assistant. 

In the fitting of the operating room two plans are offered; one upon 
the design of a general surgical operating room, accomplished by 
having a cemented or inlaid floor, enameled walls and ceiling, enam- 
eled (usually white) iron chair with leather fittings, enameled iron cab- 
inet, etc., with glass for all shelf work. These fittings are all obtain- 
able and make an admirable outfit for anyone who cares to go to that 
extent. 

The other plan admits of cheerful surroundings; hard wood floors 
with rugs, pleasing draperies and pictures with the use of glass wher- 
ever instruments are to come in contact with tables, brackets, etc. Several 
illustrations of offices may be found in the pages of the Items of In- 
terest, Vol. XXI, which would give many valuable ideas to beginners 
regarding the fittings of an office. 

Difference of opinion exists as to the proper size of the operat- 
ing room; this need be no larger than is required for the operator to 
stand by the operating chair within easy reaching distance of the in- 
strument cabinet, dental engine apparatus and electrical equipment; 
much time is saved by having everything within easy reach. When 



THE MANAGEMENT OF AN OFFICE PRACTICE. 



485 



a larger room is used this same arrangement should still be maintained 
about the chair while other appurtenances, such as an office laboratory 
work-bench, tables for porcelain furnaces and an office desk may be 
introduced. 

While many beginners may not plan to make a start in what today 
is considered a thoroughly equipped dental office, yet sooner or later 



Automatic 
Switch 




Fig. 329. 



each will come to the point where he will desire to so equip his office 
and he will find many labor and time saving devices at his disposal. 

Electricity admits a large field of application, used as it is in the 
dental engine, lathe, sterilizer, annealer, heaters of various kinds, 
syringes, both air and water, cauteries, etc., to say nothing of the light, 
illuminating the room and providing by low power lamps for oral, and 
by higher power for antral examinations. 



486 THE MANAGEMENT OF AN OFFICE PRACTICE. 

Compressed air is another most useful ally. A convenient tank of 
the capacity desired may be placed either within the operating room or 
in a place as far removed as the operator wishes. This tank may be 
filled by means of either hand, foot, electric, or hydraulic pump (Fig. 
329). The latter two keep the pressure at the full capacity of the tank 
— operating automatically as the air is used. 

The uses of compressed air are legion ; primarily, with the air syr- 
inge attached, any force — up to the capacity of the tank — may be reg- 
istered upon the dial, giving a continuous "chip-blower" action. If 
this syringe be supplied with the hot air electric coil attachment, by the 
turning on of. the current, regulated to any degree of heat desired, the 
air becomes a warm blast. 



r- j 1 n ^ - - - , — — 



s35eSEe= 




Above cut shows its application to the hand-piece. 

Fig. 330. — Engine Hand Piece — Chip Blower. 

This instrument keeps the field of operation free from debris, permits of con- 
tinued operation, thereby shortening the time at least 50%. It also minimizes 
the pain produced by the heat due to the friction of the burr in excavation. 

A very practical compressed air syringe attachment has been de- 
vised by Dr. F. T. Van Woert, of Brooklyn, N. Y., and manufactured 
by L. Green, of New York, N. Y. (Fig. 330). 

It consists of a very fine silk covered tube, leading from a con- 
trolled outlet to an atomizer nozzle attachable to the engine hand-piece. 
This gives a direct blast of air upon the surface requiring operation, 
freeing the area from debris of cutting and acting as an obtunder by 
overcoming the heat incident to the friction of the burr in cutting. 

Both electricity and compressed air may be controlled upon one 
switch-board (Fig. 331) within reach of the operator's hand while 
standing at the chair. 

In choosing an instrument cabinet certain things should be con- 
sidered, whether the cabinet be an inexpensive or a costly one; com- 
pactness, adaptability to personal needs, and, if fitted for medicines, 



THE MANAGEMENT OF AN OFFICE PRACTICE. 



487 



that there should be provided for them a separate compartment — one 
which will as effectually as possible prevent any odors from escaping. 
Manv practitioners keep medicaments in common use in their re- 




Fig. 331. 

spective vials under a glass cover. No office is atttactive if permeated 
with odors of any kind and the greatest care should be exercised to pre- 
vent their presence. 



4SS THE MANAGEMENT OF AN OFFICE PRACTICE. 

Running water is essential in the operating room. Fountain cus- 
pidors may be obtained in great variety, suited in price to any purse, 
and offering one of the most indispensable aids to the operator. This 
may be stationary or attached to the chair. A wash basin should be in 
plain sight that the patient may be assured that the operator follows 
out the necessary ablutions before each operation. 

The prosthetic laboratory should be within easy communication, 
but sufficiently removed from the other rooms to insure freedom from 



^L .. 

{Home 
Business 

f Home 

Telephone i 

(. Business 

Reference 

REMARKS. 



Fig. 332. 

odors or noise reaching them. The description of the fitting of the 
laboratory is best delegated to works upon prosthetic dentistry. 

If extraction forms a part of one's practice, a separate room should 
be provided for the specific purpose, fitted with the necessary chair, 
anesthetizing apparatus, cabinet, running water, etc. 

RECEPTION OF PATIENTS. 

The manner of the reception of patients should be given careful 
consideration. The beginner will naturally commence his operations 
upon such of his personal friends and acquaintances as seek his care. 
These in turn will be the means of sending others. The referring of a 
new patient, by either friend or fellow practitioner, should always be 
acknowledged by note or in person. 

When a practice has assumed normal proportions, a systematic 
record should be at hand to give the necessary data regarding each pa- 



PERSONAL TREATMENT OF PATIENTS. 489 

tient. To obtain such record the following method is advised: A 
new patient making his first visit is confronted with the following card 
(Fig. 332) which is filled out and filed in a cabinet (or drawer) and 
the reference given looked up; if satisfactory, much is gained in 
establishing cordial relations and the possibility of financial loss 
greatly diminished. 

PERSONAL TREATMENT OF PATIENTS. 

The success of an operator is commensurate with his ability to ' ' meas- 
ure up " to the needs of those who require his services. No two patients 
can be treated alike; some are particularly nervous and should be given 
every assistance in their endeavor to overcome the condition. Help 
such to think of something other than the operation itself. Some time 
is well spent if used for the patient's good in this manner. Allow con- 
versation to pass to a congenial channel, while progressing as rapidly 
as possible with the operation required. Much more can be done 
upon such cases with this procedure than could otherwise be accom- 
plished. In fact, many patients will voluntarily offer to pay for extra 
time and labor thus spent in their behalf rather than endure the stress 
of a strenuous sitting. 

On the other hand there are those who can endure any operation 
with little or no ill effect. Upon such the operator may proceed with 
no hesitation. Patients appreciate the care that is paid their in- 
dividual peculiarities. There is no surer way to build up a practice 
than by such treatment as this, added to sincere, loyal service rendered 
and honest operations performed. 

Children should receive the same consideration as their elders. 
Dr. Ottolengui, when questioned regarding his apparent success with 
children, expressed his belief that it was due to the fact that he treated 
them like "grown folks;" and, he added, the longer he practiced the 
more he treated "grown folks" like children. 

A little one may come to an operator for the first time with no pre- 
vious knowledge of or dread concerning a pending operation. The 
utmost care should be exercised to prolong that condition of mind. 
Let a child once acquire a dread of a dental visit and a serious handi- 
cap is placed upon the effective service of the operator — a handicap 
which years of diplomacy may be necessary to overcome. If a child 
receives other than the most considerate care in the hands of an opera- 
tor he has only himself to blame for much unnecessary trouble. It has 
been most wisely said, " Take heed lest ye offend one of the least of these 
little ones." The young practitioner should consider that these are 



4Q0 THE MANAGEMENT OF AN OFFICE PRACTICE. 

the ones who, if treated carefully and conscientiously, are to be the 
mainstay of his later practice, and the ones whose operations he will 
look back upon in after years as his long standing successes. 

ASSISTANTS. 

The subject of assistants has already been referred to; it seems 
wise, however, to lay some stress upon the advantage of the presence of 
some one — preferably a lady assistant — at the chair to render aid to the 
operator, care for the personal comfort of the patient and assist in 
innumerable ways in furthering an operation, thus saving time for 
both operator and patient. 

Great aid is found in having such an assistant trained to select 
and handle instruments; provide treatments; prepare cement and amal- 
gam fillings ready for insertion and assist in the operation of filling; 
understand the mechanism and control of the electric switch-board 
and attend to it if desired during an operation; prepare gold for filling 
purposes and assist in carrying it to the cavity and malleting if desired; 
manipulate impression material preparatory to taking impressions; 
care for the cleaning and sterilizing of all instruments after an opera- 
tion and note their return to their proper places. To these duties 
some add the making of inlays and kindred matters. 

A comparatively new field has opened, also, for a trained assistant 
in the occupation of a " dental nurse. " This has been fully described 
by Dr. M. L. Rhein, of New York, before the New York State Dental 
Society in an essay at the May, 1903, meeting; (see Dental Cosmos, 
Vol. 45, p. 628). The duties of such a nurse include the treatment of 
pyorrhea cases as well as the general prophylactic treatment of the 
oral cavity under the direction of the dentist. Such an assistant is ex- 
ceedingly valuable and in time will become an almost indispensable 
adjunct to the general office practice. 

UTILIZATION OF TIME. 

The important assets of a dental practitioner are his skill — the 
result of his training and education — and time. To misuse either is to 
fail to attain the highest possible success. 

Primarily, a beginner should endeavor to fill his time full. Ar- 
range for definite hours of work and fill those hours; if not occupied 
with the immediate care of patients — for all will not be blessed with an 
abundance at once — consume the time either in experimental work upon 
lines already laid down in college, or in study. As time goes by less 
and less- opportunity will present itself to the busy practitioner and he 



UTILIZATION OF TIME. 49 1 

looks back with regret upon time wasted when it might have been used 
to advantage. Do not be afraid to accept work even if the most mod- 
erate compensation is to accrue. Consider early practice in the light 
of valuable post-graduate experience and count the cost of apparent 
loss as chargeable to a personal " profit and loss " account. Be ready to 
make sacrifices for the good of others at all times, but especially now 
when time is not of such value as it will be later in practice. Many 
young practitioners accept infirmary and dispensary positions with 
little or no monetary compensation and reap golden harvests of experi- 
ence. 

As practice increases time becomes more valuable and justly should 
be devoted to the personal clientele. Here comes an important con- 
sideration; many men seem to feel that their own time is the only 
thing to be considered. Just as much importance should be attached 
to the time of the patient. As is indicated by the appointment card 
(Fig. 333), a patient is given an appointment for a definite day and 
hour; that hour belongs to that patient and should be as nearly as 
possible fulfilled to the minute. Habit can accomplish much in pre- 
paring for the proper arrangement of a day's work so that the various 
appointments may not conflict or overlap too greatly. Nothing but 
a serious complication is a sufficient excuse for the consuming of one 
patient's hour for the benefit of another. It is just that a broken 
appointment, i. e., one broken without due notice, should be charged 
for, and it is equally just that a patient should receive full value in time 
for an appointment set, and without delay. There are occasions when 
a patient's time may be of vastly greater commercial value than the 
operator's and if the rule of charging for "broken appointments" were 
reversed and the dentist were the one to be charged for unfulfilled 
obligations, the full force of the justice of this statement would be 
acknowledged. 

EXAMINATION RECORDS. 

Too great value cannot be placed upon accurate records of all 
operations performed. Three forms of examination cards are here 
given, any one of which is ample for the requirement, and a choice of 
which is a matter of individual taste. (Fig. 344, Nos. 1, 2 and 3.) 

When a patient first presents himself, in addition to the reference 
card already mentioned (Fig. 332), the results of the oral examination 
should be recorded and filed in proper case or cabinet in alphabetical 
order. This card may be kept separate from record cards of opera- 
tions performed, or used as both examination and record card till filled, 



40 2 THE MANAGEMENT OF AN OFFICE PRACTICE. 

when a second card for the same patient, marked Number 2 on its 

upper left hand corner, may be substituted and the old card filed away. 

Some practitioners dispose of old cards, but it is a wise practice 

to tile all such away so that at any future time a consecutive history of 



Telephon e 

"m ..~ 

Has an appointment with 

'£>.-&. S., 

.A V E N U E , 



A CHARGE WILL BE MADE FOR ALL APPOINTMENTS BROKEN 
WITHOUT TWENTY- FOUR HOURS' NOTICE. 



.J?..... _____ ___ 




/Ae... 






.-...€&€„ 






mm,*?. 


.__£_yW:«««, 

IF UNABLE TO KEEP THIS APPOINTMENT PLEASE GIVE DUE NOTICE, 

OTHERWISE CHARGE WILL BE MADE FOR THE SAME. 

CONSULTATION HOURS FROM 4 TO 5 P.M. 



Fig. T>Zr — (Appointment Cards.) 

every operation performed may be at hand. Many times these records 
are invaluable for legal purposes if any question or statement should 
arise demanding enlightenment or verification. Also, much value has 
been given them as means of identification of those who have lost their 
lives by accident. 



EXAMINATION RECORDS. 

Examination Blank No. i. 



493 



DATE 




(Front) 





z 

C5 
UJ 






















































1 











































































Fig. 334. — (One oi three Examination Blank Forms.) 



404 



THE MANAGEMENT OF AN OFFICE PRACTICE. 
Examination Blank No. 2. 










M$ 



M) 



Suggested by S. H. GuiLFORD, A. M., D. D. S. 



Examination Blank No. 3. 

Date 190 

mmmmvmmm 

Examination of M 

teeth. 

Remarks: 

Fig. 334. — (Nos. 2 and 3 of Examination Blank Forms.) 




DAILY RECORDS. 495 

DAILY RECORDS. 

As each operation is performed it should be marked upon the dia- 
gram and either by sign or number its character recorded upon that 
part of the chart assigned for such record. This should be done 
immediately to avoid error. Some practitioners make no further 
daily record than this; others prefer to add a record upon a separate 
daily record card (Fig. 335) showing all operations done during the day, 
which, when transferred to the proper accounts, may be filed away 
among a collection which may be referred to at any time for informa- 
tion regarding any particular day's transactions. Still others make 
a record in a daily record book. As each patient's operation is com- 
pleted the time consumed is marked, operations indicated, etc. The 
advantage of the daily record book is that it gives an opportunity to in- 
sert every important event of the day, as, for instance, the visit of a 
patient to pay a bill or to leave an important message which should 
receive prompt attention at the end of the day's duties. A portion of a 
page of such a record may include items as follows: 

Monday, December 17, 1906. 
8:30. John Jones. 

Root treated | 2 

1 Amalgam | 8 dis. 

Bill paid $18.00 
9:30. Mrs. N. Smith. 

1 Gold I 4 mes. cor. 

(Send appoint, to 

Miss Smith for Jan'y.) 

Reference to various teeth should be made by numbers as indicated : 

Upper 
8 I 7 I 6 I 5 1 4 I 3 I 2 I 1 I 1 I 2 \ 3 I 4 I 5 I 6 [ 7 | 8 
8 I 7 I 6 I 5 I 4 I 3 I ^ I 1 I 1 I 2 I 3 I 4 I 5 I 6 I 7 I 8 

Lower 

The various surfaces should be affixed. 

CARD SYSTEMS. 
All these record cards demand system and today little in the 
way of business method is not applicable to systematic arrangement. 
That systems are time savers is an undoubted fact. Such being the 
case, there is no excuse for their non-adoption. There are many 
laudable systems which may be found on sale at the various dental 
depots. One system, arranged by Dr. Guilford, of Philadelphia 
(Fig. 336), comprises a full set of cards, with guide cards, and places 
arranged for the tabulation of all necessary data including charges, etc., 



400 



THE MANAGEMENT OF AN OFFICE PRACTICE. 




NAME. REMARKS. ' 


CHARGES. 



































































































Fig. 335- 



CARD SYSTEMS. 



497 



thus doing away with all necessity of other book-keeping. Other 
systems have this same object in view. This feature appeals to many 
while others prefer to have no record of charges upon cards. 

The cards in these systems are usually divided into three sections 
each arranged alphabetically; the first division is for cards of patients 
whose operations are incomplete; second, for those whose operations 




Reduced Illustration of Guilford's Tin Case Outfit. 
Actual size, 5 inches wide, 8% inches long, 7% inches high. 

The accompanying method is an adaptation of the Card Index System to the 
use of the dentist. It takes the place of the Ledger, Cash-book and Bill-book, 
all of these accounts being kept on separate cards in the same box under 
suitable headings. 



Fig. 336. 



have been completed but whose bills are not paid; the third for com- 
pleted cases whose accounts are closed. 

The advantage of having an added record in book form is that it 
gives a duplicate in case a card should be mislaid or destroyed, and also 
affords an opportunity to have at a glance all data desired for long 
periods. The following (Fig. 337) is a page from a loose leaf ledger 
which is an admirable example of what concise records may be. This 
page has 45 lines upon it, but the number maybe made whatever is 



4QS 



THE MANAGEMENT OF AN OFFICE PRACTICE. 



Remarks. 




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NOTIFICATION OF PATIENTS. 499 

desired. If books are kept no charges need be displayed upon the 
cards themselves. 

Another excellent system is that of having a set of envelopes to 
be filed alphabetically. These are intended as a depository for inlays, 
crowns or dentures ready for insertion or for whatever is of any personal 
interest or value connected with a patient, such as X-ray skiagraphs, 
anomalous teeth, etc. Whatever is deposited within the envelope is 
marked upon the face under the patient's name for immediate reference. 
In this day when so many are using the impression method of preparing 
both gold and porcelain inlays this system commends itself as the re- 
sultant dies may be filed away in their proper envelopes, and duplicate 
inlays may be made at a moment's notice, if required. 

NOTIFICATION OF PATIENTS. 

The gratifying increase in prophylactic measures in dental prac- 
tice today makes it essential that a distinct supervision of the patient's 
visits should be maintained by the attending dentist. To regulate 
these visits some system is necessary as some patients require more 
frequent examinations than others. There are some practitioners 
who expect a visit from their patients at least once a month. The 
results which follow such a course are wonderfully satisfactory in pre- 
serving the patient's teeth. Others extend the time to two, three and 
six months. Few patients, if any, should be allowed to go without 
examination for a longer period. Several plans are in vogue to accom- 
plish the supervision sought. A simple one is to have one card for 
each month in the year on file. When a patient's operations are com- 
plete and he is dismissed his name is placed upon the month card 
— one, two or more months in advance — with the date and time of day 
preferred. Just prior to the first of every month the next month's card 
is taken out and the notification cards transmitted. (Fig 338.) 

This month's card then becomes " ancient history" and the next 
month's card takes its place in the front rank to be taken up in its proper 
time. The old card, however, may be kept and the result of the 
notification noted, i. e., if the appointment is kept or not, and, if not, 
the reason given for its rejection or postponement — opportunity being 
then given for a change of date with no break in the continuity of pro- 
cedure by oversight. 

A very excellent plan has been devised by Dr. W. A. Cotton, of 
New York, to meet these several card requirements upon the patient's 
original record card (Fig. 339). 

This gives the months upon the upper margin with the dates just 



;co 



THE MANAGEMENT OF AN OFFICE PRACTICE. 



M 



THE CUSTOMARY INTERVAL HAYING 
ELAPSED SINCE YOUR LAST CALL, I APPOINT 



FOR AN EXAMINATION. 

SHOULD THIS TIME PROVE INCONVENIENT TO YOU, 
KINDLY INFORM ME AND I WILL MAKE ANOTHER 

APPOINTMENT. 



VERY TRULY YOURS, 



AVENUE 



Telephone.. 




cue ue<p /o tnJ-cwrn is&ic cAcct cue Accue cc/i/ie^c^n/ec/. _. 

/Ae ccc.. e ci&ctt /a ea"cc?ncne <u<c-cck leecA{ 

vM-cn/nd Acwcruz e/cr/idec/ dc<nee i/c-tcn /cede ccc/u 

iIsA&it/c/ /Acd /twelve cnco / n / vwn<ce'n/ Acric/Zu ccc/wcde ccd ctl 
eimce, /Ace/ cue vnecu <z, / Kvcma,<e ccnei/Ae* c/cclet 

iJ&ewtei *>/)<&.. 



Fig. 33S. — (Notification Cards.) 



NOTIFICATION OF PATIENTS. 



50I 



underneath. Two little clips are used, one solid and colored red to be 
placed upon the month desired for the next appointment; the other a 
cut out clip to show the day. To this might be added a third to indicate 
a special hour if desired. 

That the practice of continuous appointments is a growing one is 
certain, and to the intelligent public it is a great blessing, as it pro- 
vides constant care of their dental welfare with no personal obligation 
to remember the proper periods between visits and an assurance that, 
barring accidents, their teeth will be kept in the best condition and in 



JAN. FEB. MAR. APR. MAY JUNE JULY AUG. SEPT. OCT NOV. DEC. 

t 2 3 A 5 6 7 8 9 1 O 11 1 2 1 3 1 A 1 S 1 6 1 7 1 8 19 20 21 22 23 24 25 26 27 28 29 30 31 


NAM E 


ADDRESS 


190 


No To Services Dr. Cr Notifications 


| 




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! 
















































































1 








i 





Fig. 339. — (Chart of teeth upon reverse side.) 

the most economical manner. When the practice becomes general 
we may expect to find less and less prosthesis and more and more 
prophylaxis. 

FEES. 
The subject of fees is a difficult one to discuss from any stand- 
point and especially so in dealing, as is the intention of this chapter, 
with under-graduates about to start upon their professional career. I 
stated at the opening of this chapter that one need not expect to grow 
wealthy practicing dentistry. Wealth, however, is a flexible term 
and I must leave that to each individual. Charges for services should be 



502 THE MANAGEMENT OF AN OFFICE PRACTICE. 

computed upon the basis of several considerations; first, "How much is 
the operation as I have performed it worth, considering all things?" 
This last phrase covers much ground. The beginner does not expect 
to value his time as highly as that of the man who has practiced for 
years, nor are his services as valuable in result — except in rare cases — 
as those of the more experienced. Hence the fee for the same opera- 
tion by one man need not necessarily be the same as that of his fellow 
practitioner. 

Environment has a bearing upon fees; a man in a small village with 
little expense can afford to charge less than his confrere in costly sur- 
roundings with proportionate increased expenses of a city practice. 

Another very important consideration is this: "Can this patient 
afford to pay my usual fee ?" Many a time in making up the estimate 
of the value of an operation w T ill this question obtrude itself and it must 
be met conscientiously. There should be no such thing as a fixed and 
unalterable price for an operation. There are some who will need 
your care; give it cheerfully, and, whether or not the exact remunera- 
tion in dollars and cents results, the satisfaction of duty performed will 
always remain with you and the successful building up of a practice will 
be assured. 

The basis of calculation of fees differs with different men. Some 
charge for each filling, denture, etc., rating the fee according to the size 
and character of the operation; others charge a certain fee for an hour's 
services, not considering the character of the operation performed. 
There are faults in each system, and the only satisfactory one seems 
to be in a combination of both. 

That some operations, while taking a short time, may be exceed- 
ingly arduous upon the operator yet extremely valuable to the patient 
is an accepted fact; and the question arises should such an operation 
be charged for upon the same basis as one which, while taking con- 
siderable time, is neither a severe task for the operator, nor of great 
value per se to the patient. 

Then, too, some operators are rapid in their operations and ac- 
complish much in an hour of thoroughly satisfactory work. A con- 
frere, with the same conscientious care and results takes twice as long. 
Should they receive the same compensation? 

STATIONERY, BILLS, ETC. 

It has been said that "we are judged by the company we keep" 
and a professional man is often rated by the stationery he uses. This 
should be as neat and unobtrusive as possible. Anything beyond one's 



STATIONERY, BILLS, ETC. 



5°3 



O 



p 






o 






10 



<^ 
U 

.-* 

"3 

Si 
o 



« 



fi 



Fig 340. 



504 THE MANAGEMENT OF AN OFFICE PRACTICE. 

degree and address is unnecessary upon professional cards or note-heads. 
The addition of " Dental Surgeon" or "Surgeon Dentist," etc., is 
needless except as a covert attempt to enhance by the term the degree 
which should need no such enhancement to sustain its professional 
dignity. 

The rendering of bills for professional services may be accom- 
plished in several ways to advantage. Upon the bottom of the bill a 
clause is placed which reads " Bills rendered upon completion of opera- 
tions" (Fig. 340). 

This may be a rule from which deviations are permissible. Many 
prefer to render statements for all work accomplished during a month; 
others at the end of two months; still others at the expiration of six 
months, in which case June 1st and December 1st are the dates pre- 
ferred. 

Questions arise from time to time regarding the best manner of 
rendering a bill; should such be itemized or not? This must be left to 
the practitioner to decide for himself. 

Some prefer to enclose with the bill, for the exact information 
of the patient, a chart showing just what has been done — practically a 
duplicate of the record card — indicating the time spent upon and the 
charge for each operation; others enclose the record card but omit the 
individual item charges; others omit all record cards (unless requested 
for them) feeling certain that their patients have all confidence in their 
honest intentions in rendering statements. 

When bills have been prepared an accurate alphabetically arranged 
list should be made with the amounts affixed. As returns are received 
the name and amount should be erased from the list and the credit re- 
corded in its proper place. When subsequent bills are required to be 
rendered, delinquents are thus easily traced and duplicate statements 
marked as such. Failure to respond by a client places one in the posi- 
tion where he may require either the services of a collector or, in ex- 
tremis, a lawyer to enforce a settlement. 

When all is said the great secret of the management of a success- 
ful office practice lies in the spirit of the well-known lines: 

"To thine own self be true, 
And it must follow, as the night the day, 
Thou canst not then be false to any man." 

Exact of yourself the highest standards of attainment, ideals and 
culture. Strive to live up to these standards and the result will be 
in other hands than yours. 



CHAPTER XXXI. 
ORTHODONTIA. 

BY HERBERT A. PULLEN, D. M. D. 

I. DEVELOPMENT OF THE DENTAL ARCHES, OCCLUSION AND 

ARTICULATION. 

Orthodontia, as a progressively advancing science, embraces within 
its sphere much more than the art of correction of malocclusion, 
since diagnostic considerations have become of such import as to de- 
mand a deeper insight into the physiological processes of the normal, 
and the etiological factors of the abnormal development of the dental 
and maxillary arches, and adjacent internal anatomical structures, 
together with their relationship to the contour of the face. 

In the light of recent advances in the treatment of dental and 
maxillary deformities in very young children, orthodontia must be 
viewed from the standpoint of such early developmental processes 
as precede occlusion of the second dentition, which by their normal 
attainment, provide for the harmonious and proportionate develop- 
ment of the maxillae and related structures, or which, by their abnor- 
mal tendency, cause insufficient or disproportionate development in 
the same regions. 

If the normal in the development of the dental arches and related 
structures occurs, normal relations of occlusion are inevitable; if, 
through any cause, development in these regions is arrested, the ab- 
normal in occlusal relations must supervene. 

Arch Development a Primary Factor. — Occlusion, whether 
normal or otherwise, being thus dependent upon earlier developmental 
conditions, is not the factor of primary import in the study of orth- 
odontia, since it is governed entirely by certain factors in develop- 
ment which precede its attainment by several years. 

From the earliest infancy to old age, the problems of malocclusion 
are problems of the abnormal in development, the study of the etiology 
of which alone reveals the inception and causative factors of the result- 
ant malocclusions. 

Note. — A large number of the cuts for the section on Orthodontia have been supplied 
through the courtesy of "Items of Interest," and the "Dental Cosmos." Credit should 
also be given to Mr. Phil. J. Knapp, of Buffalo, who made all the photographs. 

505 



^OO 



ORTHODONTIA. 



A proper comprehension of the field of orthodontia should include 

these considerations in its definition, which, in brief, is as follows: 

Orthodontia is that science which treats of the etiology, diagnosis, 

and treatment of the abnormal in development of the dental and maxillary 

arches, and of their relation to asymmetrical contour of the face. 

Normal Arch Development.— The recognition of the dependence 
of the normal function and development of the second dentition upon 
certain physiological factors of the primary dentition necessitates a 
knowledge of the sequence of developmental processes leading up to the 
eruption and attainment of normal occlusion of the permanent teeth. 

The Arches of the Temporary Teeth.— Inorder to have a logical 
and chronological succession of recorded observation of facts, it is 
necessary to study the arch at its latest period before the eruption of 

any of the permanent teeth, at 
a time when the deciduous 
teeth are all in situ, and certain 
physiological processes are 
about to take place subsequent 
to the shedding of these teeth 
and their replacement by the 
permanent set; these changes, 
according to the degree of per- 
fection of their physiological 
performance, having much to 
do with the normal or abnor- 
mal development of the second 
dentition. 
Many cases of malocclusion date their inception back to the time 
when these processes are taking place, and a proper cognizance of 
them would suggest that assistance be given to these natural processes, 
if necessary to intervene, rather than to hinder or subvert them through 
ignorance of their normal function, and consequent ill-advised treat- 
ment of certain conditions which may present. 

Fig. 341 shows a perfect development of the deciduous teeth, in nor- 
mal occlusion, at the age of four years, at which time all of the deciduous 
teeth are in position and accomplishing the function of mastication 
to the degree necessary for the nutrition of a child of this tender age. 
The retention of these teeth until the initiative in eruption of the 
permanent successors has taken place, is a feature of great importance 
in its bearing upon the normal development of the arches of the per- 
manent teeth, since their premature loss invariably causes a retardation 




Fig. 341. 



DEVELOPMENT OF THE DENTAL ARCHES. 



507 



of development of the arch which is always productive of a more or less 
serious malocclusion of the permanent teeth. 

All of the laws of occlusion which pertain to the preservation of the 
integrity of the permanent arches of teeth are in evidence likewise in 
the arches of deciduous teeth, both as to the interdependence of one 
arch upon the other for the preservation of form and normal cusp inter- 
digitation, and to the normal growth and functional activity necessary 
to the completion of the second dentition. 

Occlusal Relations. — It will be observed that there is a slight over- 
bite in the incisor region, and that each upper central incisor overlaps 
the labial surface of the lower central and one-half of the lateral in- 
cisor; each upper lateral incisor overlapping the distal half of the labial 





Fig. 342 



Fig. 343- 



surface of the lower lateral incisor, and the mesial incline of the lower 
cuspid. 

The antero-posterior interdigitation of the cusps of the cuspids, 
and first and second deciduous molars is likewise conformative to a 
normal occlusion and arrangement as in Fig. 342. 

It is well known that the integrity of the arches of the deciduous 
teeth is a very important factor in the normal development of the max- 
illa and mandible, and in the production of normal occlusion of the 
permanent teeth. 

Developmental Spaces. — While the deciduous arch still retains 
its full complement of teeth, between the second and fifth year, the co- 
ordinate and coincident growth of maxilla and mandible are taking 
place not only in the forward, downward and lateral development, 
but in an interstitial growth in the alveolar process and maxillae, which 
is evidenced by a separation of the deciduous incisors as development 
progresses. 



508 ORTHODONTIA. 

Fig. 343, illustrates the arches of deciduous teeth in occlusion just 
previous to the eruption of the permanent incisors in a patient six 
and one-half years old, a case in which the anterior development of the 
process has taken place normally, as noted by the spacing between the 
deciduous incisors. When the dental arches present this appearance 
just prior to the eruptive period of the incisors, there is every assurance 
that the eruption of the permanent incisors will occur without crowding. 
Sectional Development. — The maxillary arches do not develop 
uniformly, as might be supposed, but in sections corresponding to the 
periods of eruption of the different teeth. For example, the incisive 
region increases in width at the time of the approaching eruption of the 

incisors, above and below, the 
arches lengthening at about the 
same time, for the accommoda- 
tion of the first permanent mo- 
lars, as in Fig. 344, which is a 
picture of the same mouth as in 
Fig. 341. at the age of six years. 
At this age, the alveolar pro- 
cesses have likewise grown down- 
ward and upward, and the first 
molar teeth have come into occlu- 
sion, holding the dental arches 
Fig. 344- the proper distance apart, afford- 

ing new and broad masticating 
surfaces for use during the shedding of the deciduous teeth, and by 
their deep cusp interdigitation, accentuating the perfect mesio-distal 
registration of the dental arches, which the deciduous teeth initiated. 
The later eruption of the bicuspids and cuspids is in accordance 
with similar developmental processes which have been going on in the 
lateral halves of the arches anterior to the first permanent molars. 
The greatest development of the arches after this period takes place 
in the region of the second and third molars as they erupt into positions 
of occlusion with their antagonists in arches in which the function of 
mastication is up to a normal standard. 

Occlusal Relations of Permanent Teeth. — A proper understand- 
ing of the normal in occlusion of the permanent dentition enables the 
diagnostician to determine by comparison, the abnormal variation, not 
not only in cusp interdigitation, but in arrested development of the 
dental and maxillary arches, the etiology of which may date back to 
the earliest period of childhood. 




DEVELOPMENT OF THE DENTAL ARCHES. 509 

Anatomy, or normal structure, and physiology, or normal function, 
form the basis of the science of medicine. It would be impossible to 
diagnose and treat pathological conditions without a correct knowledge 
of the normal structure and function. 

The fulfillment of natural and normal development in the dental 
and maxillary arches in the completed dentition constitutes a normal 
and ideal relationship of occlusion of the teeth from which it is possible 
to note deviations in malocclusion, and a guide for comparison in the 
restoration of normal conditions, viz., normal occlusion. 

The characteristics of this normal dental and maxillary develop- 
ment, including the normal development of adjacent structures, are 
necessarily specified and limited, and may be comprehended in the 
following definition. 

Normal Occlusion is a condition oj perfect relationship existing be- 
tween the normally formed and arranged teeth of normally developed den- 
tal arches when in antagonism, the mandible being in its farthest posterior 
position, and in exact median register with the maxilla, and both in normal 
relationship with contiguous tissues. 

A Malocclusion is any variation from a normal occlusion either in 
size, shape or relation of dental arches, or perversion of inclined cusp 
planes. 

Normal occlusion, in the ideal, is seldom found in any type of in- 
dividual, although the approximation of it in many cases varies but 
little from the ideal anatomical occlusion. 

Characteristics of Normal Occlusion. — Fig. 345 exhibits a skull 
in which normal occlusion is present, and in which the following 
characteristics may be noted : 

1. The normal shape and size (according to type) of each arch. 

2. The normal position of each tooth in each arch. 

3. The normal shape and size of each tooth (varying with type) in 
each arch. 

4. The normal relationship of each arch to the other, and of the 
occlusal inclined planes of the cusps of the teeth in one arch to those of 
the other. 

The bilateral arrangement of the muscles, the shape of the arches 
of teeth, and their harmonious relation to each other; the form, size, 
and position of the teeth with their cusps interdigitating for mutual 
support, the proximal contact, the upward curve of the ramus, and the 
relations of the occlusal planes, all serve the purpose of increasing the 
efficiency of the organs of mastication, by providing the means, whereby 
a co-ordination and equilibrium of forces are secured, which are 



5IO ORTHODONTIA. 

essential for the preservation and function of the organs themselves, 
as well as for economy of force, and the production of lines of beauty 
not possible in any other arrangement. 

In examining the interdigitation of the teeth upon each lateral 
half, it will be seen that each tooth has two antagonists in the opposite 
arch, except the lower central incisor and upper third molar; this 




Fiq. 345. (Broomell.) 

arrangement not only providing the greatest support for the teeth 
individually and collectively, but also allowing the inclined planes of 
the cusps of bicuspids and molars the best opportunity for articulating 
during the lateral excursions of the mandible. 

Relations of Inclined Planes. — Beginning at the median line 
of the dental arches in normal occlusion the following cusp rela- 
tions may be noted which are conformative to the normal in the 
bucco-occlusal relations of the teeth. The upper central incisor is 



DEVELOPMENT OF THE DENTAL ARCHES. 511 

in occlusal contact with the incisal edges of the lower central in- 
cisor and one-third to one-half of the lower lateral incisor; the upper 
lateral incisor is in occlusal contact with the remaining two-thirds 
or one-half of the incisal edge of the lower lateral incisor, and the 
mesio-incisal angle of the lower cuspid; the upper cuspid occludes with 
its mesial incline in contact with the distal incline of the lower cuspid, 
and its distal incline in contact with the mesial incline of the buccal cusp 
of the lower first bicuspid; the buccal cusp of the upper first bicuspid 
occludes with its mesial incline in contact with the distal incline of 
the buccal cusp of the lower first bicuspid, and its distal incline in con- 
tact with the mesial incline of the buccal cusp of the lower second 
bicuspid; the buccal cusp of the upper second bicuspid occludes with 
its mesial incline in contact with the distal incline of the buccal cusp of 
the lower second bicuspid, and its distal incline in contact with the 
mesial incline of the mesio-buccal cusp of the lower first molar; the 
mesial inclines of the mesio- and disto-buccal cusps of the upper first 
molar occlude with the distal inclines of the mesio- and disto-buccal 
cusps of the lower first molar; the distal incline of the disto-buccal cusp 
comes into occlusal contact with the mesial incline of the mesio-buccal 
cusp of the lower second molar; similar relations of the inclined cusp 
planes are in evidence in the second and third molars, except that the 
upper third molar has no antagonizing plane for the distal incline of 
its disto-buccal cusp. A similar arrangement of the lingual cusps of 
the upper teeth in their occlusal relations with the lower renders the 
interdigitation of cusps for mutual support still more pronounced. 

The object of this complex interdigitation of cusps is to give the 
greatest support, not only to the teeth individually, but as a whole, 
their sizes, forms and positions of cusps and inclined planes being best 
adapted for this purpose. 

Preservative Forces of Arch Integrity. — Having outlined 
the positions of the individual teeth in normal occlusion, it is quite 
important that cognizance be taken of the forces which tend to pre- 
serve this normal arrangement, viz. : 

1. The interdigitation of the cusps of the teeth. 

2. The reaction and dependence of one arch upon the other. 

3. The muscular influence of the lips, cheeks, and tongue, labially, 
buccally and lingually. 

As one arch is dependent upon the other for its regularity, it follows 
that a malocclusion in one arch implies a similar condition in the other, 
and the maintenance of the malocclusion is just as effectual as through 
the normal influence of the above mentioned forces. 



512 ORTHODONTIA. 

If the lower arch is contracted and the teeth crowded, the same con- 
ditions will be found in the upper arch as a result of the operation of 
these forces. 

Nomenclature in Malocclusion.— In order to avoid confusion in 
nomenclature the author has conformed the text to the nomenclature 
adopted by Dr. Angle, which has been in quite general use for several 
years. 

In brief, this nomenclature is based upon the variation of individual 
teeth from the line of occlusion; a tooth outside this line being in labial 
or buccal occlusion, inside of this line, in lingual occlusion; if it is forward 
of the line, it is in mesial occlusion, if in the reverse direction, in distal 
occlusion; if rotated upon itself, in torso-occlusion. Teeth which have 
elongated beyond normal relations are in supra-occlusion, and those 
which are insufficiently elevated are in infra-occlusion. 

In all branches of art, such as sculpture, painting, architecture, etc., 
a model of perfect art is chosen as a guide to reproductions which rep- 
resent the highest conceptions of a certain type, whether it be the 
Apollo in sculpture, the Madonna in painting, or the Renaissance in 
architecture. 

Normal occlusion is the highest conception of a type, not a relative 
or approximate condition. It is an ideal state of physical integrity, and 
can only be perfectly conceived in a perfect anatomical subject, which 
would necessitate, therefore, the normal, typical, and perfect develop- 
ment and relationship of contiguous tissues of the hard and soft anat- 
omy, the osseous and muscular tissues of the head and face, and the 
harmonious and proportionate development of the facial lines which 
are conformative to beauty and harmony of the profile. 

It has been suggested that the word "occlusion" alone be used 
to designate this ideal relationship; that the word "normal" is un- 
necessary, since if occlusion is anything, it is normal; otherwise, maloc- 
clusion is the proper term, but the acceptance of this term without the 
limiting characteristic which the word "normal" adds to it would be 
confusing and unwarrantable in referring to the typically ideal anatom- 
ical occlusion. 

The commonly accepted use of "occlusion" is in reference to the 
relation of the interdigitating cusps of the teeth, whether there is a 
normal, or a malocclusion present, and it may be definitely described 
as follows: 

Occlusion is the most constant static relationship of the antagonizing 
surfaces of the arches of teeth in inter digitation. 

Distinction between Occlusion and Articulation. — The svn- 



DEVELOPMENT OF THE DENTAL ARCHES. 513 

onymous use of the terms " occlusion" and "articulation" is not in 
accordance with their specifically different meanings, as generally un- 
derstood by those who have carefully studied them. 

Articulation is the relation between the antagonizing surfaces of the 
teeth of maxilla and mandible during the lateral and protrusive excursions 
of the latter, dependent upon its universal articulation at the glenoid fossa. 

There are three distinct stages of articulation, viz., prehension, 
attrition, and occlusion. The first two stages represent the mandible 
in motion, the last, the mandible at rest, the teeth being closed. 

Occlusion is the passive phase of articulation, as compared to the 
active phases of prehension and attrition. 

Occlusion represents the static, and articulation the dynamic, re- 
lation between the arches of teeth. 

Some recent writers have argued that occlusion should represent 
all that is meant by articulation in its relation to orthodontia, but such 
a generalization of the term would be absurd, and any attempts at diag- 
nosis of malocclusion from such a variable base would only result 
in confusion. However, it is impossible to completely separate these 
terms in their bearing upon the normal relationship of the arches of 
teeth, so intimately are they connected. 

A normal occlusion necessitates a normal articulation, and a nor- 
mal articulation necessitates a normal occlusion. 

The laws of articulation produced the perfectly formed arches of 
teeth, the depth of the overbite, the length of cusps, and relations of 
occlusal inclined planes, so that the definite form and positions of the 
teeth and relations of the arches known as normal occlusion was a pos- 
sibility. 

In occlusion, the lines of force are constant in their direction, in 
articulation, they are ever changing, varying as the relationship between 
the arches of teeth causes stress to be made between antagonizing 
tooth surfaces in constantly changing angles. 

Articulation. — By carefully studying the forms and positions of the 
inclined planes of the cusps of the individual teeth, the length of cusps, 
decreasing in depth from the first bicuspid to the last molar, the 
depth of the overbite, and the compensating curve of the arches, it will 
be noticed that there is a distinct relationship existing between the 
length of the cusps in bicuspids and molars, the overbite, and the com- 
pensating curves, which, as pointed out by Bonwill, serves the purpose 
of supporting the arches of teeth in all positions of articulation, and 
affords the greatest surface for the mastication of the food. 

It is not to be concluded that function primarily of the masticatory 

33 



514 ORTHODONTIA. 

organs produces this relationship of the arches, for the full develop- 
ment of the crowns and cusps of the teeth is far in advance of any sug- 
gestion of the function, and only upon eruption to occlusion do the cusps 
of the teeth come under the influence of each other in opposing arches 
in articulation and occlusion. 

On examination of the arches of teeth in normal articulation, in the 
movement of the mandible to the left from the position of occlusion the 
following articular relations may be observed, as described by Bonwill: 
"The right condyle moves forward and downward in the glenoid cavity 
one-eighth of an inch, when at its farthest limit, causing the outer and 
inner cusps of the upper teeth, from the centrals to the last molar, 
to touch the outer and inner, or buccal and lingual cusps of the lower 
on the same side — the left; and on the opposite side — the right — we 
find only the inner cusps of the bicuspids and molars of the upper, to 
come in contact with the outer of the lower, and the right central to the 
cuspid do not touch." 

In moving the mandible to the right, these positions are just reversed 

"Again, if the mandible is moved directly forward from the posi- 
tion of occlusion, until the incisors touch edge to edge, the buccal and 
lingual cusps of the upper second molars touch the buccal and lingual 
cusps of the lower second molars." 

"In order that this articulation of cusps in the above movement may 
take place, the overbite must not only be proportionate in depth to the 
depth of the grooves in bicuspids and molars, but also the curvature up- 
ward of the ramus must be in the same proportion." 

"The depth of the cusps in the upper first bicuspids corresponds al- 
most exactly with the depth of the overbite, the cusps diminishing in 
depth from first bicuspids to last molar." 

"The necessity for the touching of so many teeth during articulation 
is evident when we recall that the muscles of the jaws should act equally 
on both sides, even though but one side is in use at one time, the other 
side touching to balance the forces at work on the opposite side." 

"It is mechanical law and that of motion, to obtain a certain result 
for the perpetuation of the organs themselves, but the life of the whole 
organization, and the grooves, fissures and cusps are so arranged . . . 
that where each is in its normal position in the jaws all surfaces wear 
alike, and the shapes are kept in harmony." 

Development of Associated Anatomical Structures. — In order 
that a clearer idea of the field of the orthodontist may be engend- 
ered, a study of the internal facial anatomy from a vertical trans- 
verse bilateral section of the head, as illustrated in one of Dr. Cryer's 



DEVELOPMENT OF THE DENTAL ARCHES. 



S I S 



dissections, Fig. 346, revealing comparatively normal development of 
the maxillary arches and associated structures and sinuses, may serve to 
illustrate how closely the internal structures are associated, and to 
what extent they are interdependent for normal growth and function. 
Immediately above the floor of the hard palate may be observed a 
straight nasal septum, dividing the internal nose into two large and 
well formed meati, adjacent to which, the fully developed maxillary 
sinuses are situated. 




Fig. 346. {Cryer.) 



This normal and proportionate development of associated anatom- 
ical structures of the internal face is not a chance coincidence, but the 
result of a functional and structural relationship which is most im- 
portant to the diagnostician. 

Of first importance to the development of the dental and maxillary 
arches is the function of normal nasal breathing, which is only possible 
with properly developed nasal meati. 

Second, in importance is the function of mastication, the natural 
action and reaction of the teeth of mandible against those of the maxilla 



5 1 6 ORTHODONTIA. 

serving to further development of the dental and maxillary arches, 
and thereby assist in the development of the floor of the nose and asso- 
ciated sinuses, etc. 

Normal breathing is given first place in important developmental 
functions, because with deficient respiratory powers, as in the mouth- 
breather, the teeth seldom come into contact sufficiently to obtain the 
requisite amount of occlusion and articulation necessary for proper de- 
velopment of the arches. 

Co-ordination of Functions. — It will be therefore apparent that 
co-ordination of normal function of respiration and occlusion are the 
most potent factors in the symmetrical and proportionate develop- 
ment of the internal face, the nasal cavities and associated sinuses, and 
the maxillary and dental arches. 

Such symmetrical development of related parts implies as well the 
existence of full nutrition, and the absence of any untoward etiological 
factors which would tend to diminish functional influence or lower 
the vitality in any way. 

Any local functional and developmental disturbance may be the 
result of general systemic conditions, of lowered vitality from what- 
ever cause, so that any local pathological manifestations in diminished 
or perverted function and consequent modified anatomical structures 
should be considered in relation to the health of the whole organism. 

The association of nasal stenosis, mouth-breathing, and arrested 
development of the maxillae, and dental malocclusion, is sufficient evi- 
dence of the interdependence of function and structure in these associ- 
ated regions to convince the most skeptical of the importance of the 
study of the anatomy of the internal face with a view to the discovery 
of certain causative factors which will assist in the remedy or cure of 
abnormal developmental conditions, which require an intelligent differ- 
ential diagnosis. 

II. SYMMETRY AND ASYMMETRY OF THE FACE. 

Orthodontia has advanced beyond the teachings which its name 
might imply to the field of orthopedia to such an extent that there can 
scarcely be any orthodontic treatment which does not include ortho- 
pedic considerations. 

The restoration of esthetic facial contour through orthodontic and 
orthopedic treatment, although included in the field of orthodontia, 
may correctly be styled dento-facial orthopedia, and be defined as 
follows : 

Dento-facial Orthopedia is that art which deals with the restoration 



SYMMETRY AND ASYMMETRY OF THE FACE. 



517 



of facial symmetry through the prevention and treatment 0) abnormal 
development 0) dental and maxillary arches. 

Physical Relations of Beauty.— The broadening of the field of 
orthodontia to embrace the field of facial orthopedia has necessitated a 
closer study of the art relations of the human face with a view of ascer- 
taining those qualities of beauty which are related to the normal and 
typical in development, rather than those qualities of facial beauty 
which appeal to the esthetic faculties because of the influence of the 
mind upon the physical expression. 

Beauty is defined as "the assemblage of graces or properties which 
are pleasing to the eye, the ear, the intellect, the esthetic faculty, or 
the moral sense," "the multiplicity of symmetrical parts uniting in a 
consistent whole." 




Fig. 347- 

It has been pointed out by artists that no fixed "line of harmony" 
exists in relation to the profile, but that beauty of the face consists in a 
proper balance of the features according to type. 

Limited then, as the orthodontist is to a consideration of the physical 
relations of the various parts of the face, the qualities of symmetry and 
proportion alone, as indicated by the normal and harmonious develop- 
ment of the face as a whole, including the underlying osseous structures 
as well as the muscular tissues overlying them, can be consistently 
studied by him in the determination of the normal or abnormal. 

Facial Symmetry consists of the normal and proportionate develop- 
ment of facial contour dependent upon the corresponding development and 
growth of the underlying osseous structures and sinuses. 

Harmony of the Facial Profile. — Viewed from the standpoint 
of the artist, the harmony of proportions of the profile consists in 
a correspondence in measurement of prominent divisions of the 



<i8 



ORTHODONTIA. 




Fig. 34S. 



profile from the top of the head to the chin; from the hair to 
the bottom of the chin should measure three-quarters of the height 
of the whole head; the forehead to the root of the nose measures 
one-fourth; the nose one-fourth, and the mouth and chin one-fourth. 

A very comprehensive illustration 
of these measurements may be 
seen in Fig. 347, in which at the 
same time may be noted the corre- 
spondence of the facial curves of 
the forehead, nose and chin, and 
the normal development of each 
separate third of the face so that a 
proper balance of the face as a 
whole is attained. 

In the consideration of the devel- 
opment oj anatomical structures, the 
normal growth of tissues depends 
upon proper functional activity, and 
deficient functional activity from 
any cause is productive of structural defects in growth. 

For the full development of the lower two-thirds of the face, there 
must not only be perfect function in the respiratory mechanism result- 
ing in normal nasal breathing, and development of the whole middle 
third of the face, but also there must be proper functional activity in 
mastication, and the absence of 
any untoward influence in tooth or 
arch development, either through 
mechanical interference or local 
effects of deficient nutrition due to 
nervous or circulatory impediment 
of any kind. 

A very well-proportioned profile 
with a correspondence of curves 
of the forehead, nose, lips and chin, 
is illustrated in Fig. 348. Accord- 
ing to the principles of facial sym- 
metry, it would be expected that 

the functions of respiration and mastication were unimpaired in this 
individual in order to have produced the correlation of symmetrical 
parts of the profile as seen in the illustration. 

The middle third of the face is well developed, the nostril wide and 




Fig. 349- 



SYMMETRY AND ASYMMETRY OF THE FACE. 



519 



dilated and there was no indication upon examination of any nasal ob- 
struction or inflammation which might induce a diminution of the 
normal breathing function. 

The proportions of the lower third of the face are also so perfect 
that the prognosis of almost perfect development of the arches of teeth 




Fig. 350. (Cryer.) 



and the absence of any marked malocclusion might be made with a 
degree of certainty, and upon examination of the model of the mouth in 
Fig. 349, the correctness of this prognosis may be seen, there being but 
very slight deviation from the normal relationship of occlusion. 

Relations of External and Internal Anatomy. — A very in- 
teresting illustration of the relation of external and internal facial 



520 ORTHODONTIA. 

development may be observed in a sagittal section of a typical skull, 
Fig. 350, made by Dr. M, H. Cryer. The profile appears propor- 
tionate in the development of its various divisions, and a view of the 
internal anatomy reveals well- developed esseous structures and sinuses 
in the middle third of the face and a typically normal development 
of the maxilla and mandible, and a tongue which almost completely 
fills the oral cavity. 

Dr. Cryer has demonstrated by many sections of the frozen heads 
of cadavers that variation of the internal anatomy of the face and head 
is of such frequent occurrence that typical and symmetrical develop- 
ment of the corresponding osseous structures and sinuses of the two 
lateral halves of the head is the exception rather than the rule, thus 

accounting for such variation in develop- 
ment of the superficial muscular and 
other tissues, which are often so pro- 
nounced as to to be noticeably deformed. 
Facial Asymmetry consists of the 
abnormal and disproportionate development 
of the contour of the face, dependent upon 
a corresponding abnormal development and 
growth of the underlying osseous structures 
and sinuses. 

In the consideration of facial asym- 
Fig. 351. {Parke Lewis.) metry, as related to development, it is 

necessary to exclude the facial defects 
caused by such nervous lesions as paralysis, or the structural lesions 
of tumors, and other similar pathological manifestations not bearing 
directly upon the general laws of facial development, except such 
developmental neuroses as are admitted to be embryonic in character, 
and which, whether degenerative or not, must be taken into consider- 
ation by the diagnostician of structural deformities in any part of the 
body. 

Inequalities of Growth. — The ophthalmologist recognizes the in- 
equalities of structural growth in the variation from the normal anatom- 
ical similarity and relationship of the eyes; one eye may be larger than 
the other, or more deeply set; one eye may be higher than the other, as 
in Fig. 351, producing lack of co-ordination of function of these organs, 
and the resultant strain of the muscular tissues of the face in the effort 
to attain binocular vision is evidenced by the facial expression. 

The screen method of measuring the face, illustrated in Fig. 352, 
affords a means of determining the variations in height of the corre- 




SYMMETRY AND ASYMMETRY OF THE FACE. 



521 



sponding halves of the face, and also the variation from symmetry of 
the facial thirds, and the anatomical deviation from the central facial 
line. 

The Scope of Orthodontia. — In the study of the face, we must 
encroach upon the field of the ophthalmologist and the rhinologist in 
order to have a comprehensive idea of the normal and abnormal in 
development of the structural anatomy of the regions in which they 
are working, and the symptomatic and pathological relationship of 
diseased conditions in these regions and in those of the orthodontist. 

The facial orthopedist should never lose sight of the fact that there 
are a great many types of faces, vary- 
ing with nationality, and climate and 
environment, and that the features 
conform with great persistency to 
racial characteristics in particular. 

Inharmony of the Profile. — A 
face may be perfect in its type ex- 
cept for some slight deformity in the 
lower third which may exhibit lack 
of harmonious development. 

For example, in Fig. 353, the 
profile conforms in most of its lines 
to its type, and contains many of the 
elements of beauty in some of its 
proportions, but the apparent prom- 
inence of the lower lip offsets all the 
esthetic characteristics of the other 
parts of the face. A study of this 
profile will convince the careful observer that the apparent deformity or 
protrusion of the lower lip and of the mandible is an optical illusion, 
and that the upper lip alone is out of harmony with the rest of the pro- 
file, being retruded from the normal pose which it should occupy. 

As proof of this diagnosis, a study of the occlusal relations of the 
arches of teeth in Fig. 354 exhibits a normal relationship in the molar 
region, and an abnormal position of the upper anterior teeth alone, 
they being in lingual occlusion. 

Deformities of this nature often affect the welfare and happiness 
of the unfortunate possessors for a whole lifetime, so keenly sensitive 
are they to public notice and unfavorable comment by those with whom 
they come into daily contract. 

Any variation from normal and symmetrical development of the 




Fig. 352. (Parke Lewis.) 



ORTHODONTIA. 



two sides of the face may be detected by drawing an imaginary line 
through the center of the face from the forehead to the chin, as in Fig. 
355, in which a marked deviation from this line is noticed in the lower 




Fig. 353. 

third of the face, and caused by the malocclusion of the teeth, which 
forced the mandible to one side. 




Fig. 354. 



An examination of the profile of this case, Fig. 356, exhibits the extent 
of the deformity, the chin being considerably protruded, giving the 
individual a senile appearance. 



ETIOLOGY. 



5 2 3 



The model of the mouth of this young lady in Fig. 536 exhibits just 
such a lack of harmony in occlusion as we would expect from a study 
of the facial inharmony. 

The functions of speech and mastication are seriously impaired, 





Fig. 355. 



Fig. 356 



and were it not for the skill of the orthodontist, there would be no 
remedy for the alleviation of the deformed condition which is such 
a handicap, to the one having such a facial disfigurement. 



III. ETIOLOGY. 

Deductions From Early Symptoms of Developing Malocclu- 
sion. — The advent of diagnostic interpretations from the basis of 
occlusion has caused an earnest study of early symptoms of developing 
malocclusion, a very large percentage exhibiting such. peculiarities of 
maldevelopment of the arches as a whole, as to claim a most serious 
consideration of the possible etiological characteristics, and their prob- 
able bearing upon operative treatment of abnormal conditions present. 

The exclusion of such local etiological factors as premature loss of 
deciduous teeth, etc., in the production of small and crowded arches of 
teeth have led to the conclusion that malpositions of the teeth, indi- 
vidually and collectively, are but superficial symptoms or results of 
arrested function and development of the arches as a whole, including 
the alveolar process and underlying bone, and even extending into the 
associated nasal structures and sinuses. 

The concomitant arrest of development of the nasal cavities, and a 
diagnosis of similar local or remote etiological factors, furnishes the 



524 ORTHODONTIA. 

strongest proof of the wisdom of observing and preventing abnor- 
malities in development during the earliest period of child life, when 
functional insufficiency interferes most profoundly with the normal 
growth of developing anatomical structures. 

Very marked malocclusions of the deciduous teeth, such as pro- 
nounced protrusions, have been not infrequently observed by the 
author and others in children of two years of age and younger, exhibit- 
ing some form of functional derangement, especially in the nose and 
throat, and indicating defects in development which may be of congen- 
ital origin. 

These disturbances in development occur very early in life, and if 
remedial treatment is not instituted before the sixth or seventh year, 
or even earlier in some cases, the possibility of permanent benefit, 
especially in the establishment of normal nasal respiration, where it 
is perverted, is greatly lessened. 

Intra-uterine Influences upon Arch Development. — The 
normal development of the dental arch, including the eruption of its 
deciduous and permanent teeth and their alveolar base, preconceives 
primarily, the healthy structure and the molding and development of 
the maxilla and mandible during embryonic life, which are naturally 
dependent upon the nutritive and other conditions in which they are 
surrounded in intra-uterine life. 

It is conceded that prenatal influences, whether they be of a nutri- 
tional, functional or nervous type, have a definite bearing upon the 
metabolic processes which tend toward symmetry or asymmetry of 
development of the embryo in whole or part. 

Hare-lip and cleft palate are recognized as simply lack of com- 
plete development in the embryo through some retardation in intra- 
uterine development, the causes for which are obscure only because of 
the inability to directly trace the particular influences w^hich might 
arise from a neurotic or other tendency, which in turn affects the 
growth and development of cellular structures in those parts of the 
human organism peculiarly open to such influences. 

Talbot remarks: "The structures of the mouth and nose being 
exceedingly variable in evolution, and the structures of the jaws and 
teeth having taken an embryonic trend for the benefit of the body as 
a whole, under the law of economy of growth, disturbances of balance 
are peculiarly apt to occur here." 

"Not only is actual growth upset by the operation of this dis- 
turbance of balance, but certain potentialities are likewise interfered 
with." 



ETIOLAGY. 525 

Influence of the Pituitary Body. — "In dealing with the develop- 
ment of the palate, both pre- and post-congenitally, the relations of the 
hypophysis, or pituitary body, have to be taken into account, since it 
has been well demonstrated that this body exerts an influence over 
body growth and the structures thereto related." 

"Strain on the development of the hypophysis after birth cannot 
only produce undue growth of bone, but can also check development 
of it." (Talbot, Etiology of Cleft Palate, Sec. V, Page 195; Trans. 
Fourth Internat. Dental Congress.) 

Whatever the particular stress may be which lowers potentiality 
or retards development in the embryo, it is enough to know that such 
influences exist, and invariably affect the development of particular 
parts of the organism in greater or lesser degree. 

Post-natal Factors in Arch Development. — After birth the nor- 
mal development of the dental arch is largely a question of proper 
nutrition and function, recognizing also, the possibility of an insuffi- 
ciency of nutrition and perversion of function with which the child may 
be born into the world, and from which inadequate foundation normal 
function and normal structure are not readily developed. 

Heredity and Environment. — Just at this point it may be necessary 
to distinguish between the influences of heredity and environment, in 
order that a clearer conception of the two may be engendered. 

Quoting from Dr. W. J. Brady, "The Influence of Heredity on 
Malocclusion:" "The tendency to resemble ancestry is called 
heredity, and a character or condition that appears prominently through 
a series of generations is said to be hereditary or inherited. The 
surroundings of an organism are called its environment, and include 
every possible condition which might have any effect upon its devel- 
opment, such as food, climate, light, air, moisture, heat, cold, cultiva- 
tion, artificial benefits, natural enemies, companionship, mental con- 
dition, method of living, exercise, in fact, any and all things capable 
of exerting any influence for better or worse." 

" Heredity is the force that holds all life to its true forms throughout 
the ages, and its power is not set aside in a few years even under an 
intensely changeable environment." 

"Heredity always tends to promote the normal, the healthful, not 
the abnormal or diseased." 

"Aside from the fact that heredity promotes the normal instead 
of the abnormal, it is also very questionable if a feature like mal- 
occlusion can be transmitted at all. A violent change is much less 
likely to be transmitted than a slight one, and a bad case of mal- 



526 ORTHODONTIA. 

occlusion is certainly a great change from the normal. Weismann, the 
groat writer on heredity, gives it as his opinion after years of observa- 
tion that only slight acquired conditions are ever transmitted, and 
scientists are very cautious as to their statements of what changes 
may become hereditary and what may not." 

"If a similar condition exists in parent and child, let us not jump 
to the conclusion that the defect is inherited, but rather let us in- 
vestigate the environment. If we find contracted dental arches in 
the same family it is a sign that all members have lived upon the same 
kind of food, and all have failed to give normal exercise to the teeth 
and jaws. If nasal or pharyngeal hypertrophies -exist from one genera- 
tion to another, we will find the environment is inherited rather than 
the disease." 

Functional Influences. — After birth, the influences which tend to 
normal arch development are largely functional, influenced of course 
by environment. 

Succeeding mammary function, which is believed to have consider- 
able influence upon general developmental conditions in infancy, the 
function of mastication, and the proper use of the muscles of the tongue, 
cheeks and lips, are the most important factors in the development of 
the dental arch after dentition is complete. The exclusion of other 
factors which would tend to retard development, such as anemia in- 
fluenced by malnutrition, and other constitutional conditions, and the 
absence of nasal or post-nasal obstruction to normal breathing, are 
essential to the normal growth of maxillary structures and the proper 
sequence of functions. 

Normal Muscular Action. — As illustrative of the effect of normal 
muscular action upon the development of bone in the maxilla and 
mandible, the lines of stress in developing bone caused by muscular 
action as seen w T ith the X-ray by Walkhoff, offer sufficient evidence 
of the influence of muscular action in development, not only in embryo 
and infancy, but also during the entire period of development of the 
dental arches up to the time of the eruption of the last permanent 
tooth. 

This investigator has demonstrated conclusively that the stress 
upon the surface of the bone through the muscular attachments was 
directly related to the internal development of and arrangement of 
the bone spicules, which form themselves in lines parallel to the direc- 
tion of the exertion of the muscular force upon the external surface of 
the bone. 

Disuse of the muscles of mastication, or their abnormal use, 



ETIOLOGY. 



5 2 7 



therefore, must have its effect in the deficiency and abnormality of 
development in the dental arches. 

The disappearance of the angle formed by the rami and body of 
the mandible in certain pronounced mouth-breathers of Class III is 
an evidence of the influence of abnormal muscular action upon the 
shape of the underlying bone. 

Inflammatory Changes in Alveolar Tissues. — The thickening 
and hardening of the cancellated and cortical portions of the alveolar 
process through suppurative conditions caused by diseased teeth in- 
terferes with normal and uniform development of the bony tissues in 
which these changes take place, and no doubt are causative of some of 
the peculiarities of development of the dental arches, especially of 
tooth impaction. 



Tooth-sacs of 
permanent teeth. 



ffa 


^.-r ,K3lT^ / 


SV&i 


1 



Tooth-sacs of 
deciduous teeth. 



Periosteum of hard palate. 

Fig. 357. — Tooth-follicles for deciduous and permanent teeth, 
three months after birth. (Broomell.) 



Disease. — The influence of such diseases as rickets, syphilis, and 
others may seriously affect the development of the osseous structures of 
the maxillae. Malocclusion is peculiarly a result of pyorrhea, the 
teeth becoming elongated, and forced into malpositions through the 
undue influence of their own inclined planes. 

Abnormal Arch Development.— In consideration of the factors 
in arch development which have been stated, it is interesting to note 
the positions of the permanent tooth follicles at a period in child life 
when the deciduous teeth are unerupted, and speculate upon the possi- 
bilities of arrested development upon the permanent arches of teeth. 

Fig. 357, represents the dissected tooth folliclesof the deciduous and 
permanent teeth in the mouth of a child three months after birth, the 



5*8 



ORTHODONTIA. 




Fig. 358- 




Fig. 359. 



ETIOLOGY. 



5 2 9 



plastic tissues in the center of the cut being the periosteum covering 
the hard palate, the tooth follicles being imbedded and firmly adherent 
to the fibrous tissues laterally and anteriorly. 

The tooth sacs of the deciduous teeth are upon the periphery, 
being external to, and larger than the sacs of the permanent teeth. 
The arch of the deciduous teeth, which are nearly ready for eruption 
anteriorly, is very nearly uniform in shape and development, while that 
of the permanent teeth has not at this age even assumed any definite- 
ness of uniformity or position of its teeth, the four permanent in- 
cisors being more fully developed than the cuspids and bicuspids, 
but the lingual position of the laterals indicates that considerable 





Fig. 360. 



Fig. 361. 



arch development must take place before there will be sufficient space 
for these teeth to erupt into their normal positions in line with the 
centrals. 

If, by reason of any infantile cachexia, such as malnutrition, from 
whatever cause, arrest of arch development should occur at this age, or 
even later up to five or six years of age, the resultant effect upon the 
arch of the permanent teeth might be such as is illustrated in the two 
casts shown in Figs. 358 and 359 at the ages of seven and twenty-seven, 
in which the positions of the central and lateral incisors are seen to be 
almost identical with that of the permanent incisor follicles in the 
previous illustration. 

34 



530 



ORTHODONTIA. 



It will be observed that the adult arch in Fig. 359 did not develop 
any larger than the arch of the deciduous teeth in Fig. 358, the 
arrest of development being almost permanent except for the eruption 
of the permanent teeth into positions of irregularity, so great was 




Fig. 362. 



the functional disturbance which left its impress upon the maxilla 
and overlying processes. 

Another interesting feature about the case of this adult is that 
there was no apparent facial deformity except the slightly marked 



ETIOLOGY. 531 

deviation of the central facial line at the age of four, see Fig. 360, 
but at the age of twenty-seven, see Fig. 361, the distortion of the 
facial lines indicates serious malocclusion and maldevelopment. 

Again, in Fig. 362, is compared the upper deciduous arch of a four 
year old child, with the undeveloped upper arch of a ten year old 
child. The feature of striking interest in the case is the fact that the 
arch of the ten year old child is scarcely larger and is not more developed 
than that of the child of four with which it is compared. 

Such studies as these prove to the observer that, although the func- 




Fig. 363. 

tion of occlusion is perverted, and its beneficial influence upon the 
growth 'of the dental arches lacking, there are still present causative 
factors of the arrested development, possibly of prenatal origin, which 
must be given due consideration. 

Mouth-breathing. — One of the most serious abnormal conditions 
with which the rhinologist and the orthodontist have to deal, and one 
as intimately connected with the disturbance of normal function and 
structure in the field of the one as in that of the other, is the partial or 
complete loss of normal respiratory function through the obstruction 
of the nasal, naso-pharyngeal, and oro-pharyngeal air passages, causing 
oral respiration, commonly known as mouth-breathing. 



532 ORTHODONTIA. 

That this condition, with all of its injurious results upon the de- 
velopment of the bones of the head and face, the disfiguring of the 
features, and the undermining of the general health, is becoming more 
prevalent, one hardly needs statistics to show, in view of the great 
numbers of those afflicted with this trouble in all walks of life. 

Fig. 363 represents the face mask of a typical mouth-breather, 
the characteristic features noticeable being the open and drooping 
mouth, the short upper lip, the undeveloped nose, and undilated nos- 
tril, and the malocclusion of the teeth. 

The vacant stare especially accompanies the presence of large ade- 
noids, and is said to be caused chiefly by the stagnation of lymph 
at the base of the skull. 




Fig. 364. . Fig. 365. 

On examination of the relations of the arches of teeth (Fig. 364) 
of the patient whose face mask is illustrated in the previous figure, 
it will be noticed that arrested and abnormal development of 
the arches of teeth is in evidence, sufficient to cause a very great lack 
of harmony of the facial lines. The upper arch is narrow and elon- 
gated, the upper bicuspids and molars being in lingual occlusion, 
and the lower arch distal to its normal position, a case of the first 
division of Class II, Angle's classification. 

It has been the observation of the author that a mouth-breather may 
present a malocclusion of any one of the different classes into which it 
is possible to divide the abnormal relations of occlusion, rather than of 
only one or two of them, as has been suggested by some writers, and 
the shapes of the arches of teeth are varied, and the extent of the maloc- 
clusion measured somewhat by the degree to which oral respiration is 
resorted to. 



ETIOLOGY. 



533 




Fig. 366. 



One of the most aggravating forms of malocclusion associated with 
mouth-breathing is that of the "open-bite" malocclusion, as it has 
been termed by some writers. Lack of anterior occlusion and " infra- 
occlusion" are similar designations for the same condition. Fig. 
365 illustrates such a case 
belonging to Class I. 
There is a noticeable lack 
of development of both 
arches in this case, there 
being insufficient growth 
for the eruption of the per- 
manent teeth, especially in 
the incisor region. The 
treatment of this case is 
illustrated in Fig. 467 in 
the chapter on treatment. 
A rather late operation for 
adenoids assisted in restoring normal respiration, and the correction 
of the mal-occlusion restored the function of the arches so that sub- 
sequent development along normal lines, both of the arches and the 
face, seemed assured. 

Fig. 366 exhibits a very common form of malocclusion, Class II, 

Div. 1, found among mouth- 
breathers, the lower arch be- 
ing distal to normal in occlu- 
sion, and the shortness of the 
upper lip, and therefore lack of 
function in supporting the in- 
cisors, allowing them to pro- 
trude to a considerable extent, 
a condition which is aggra- 
vated or intensified by the 
lower lip adjusting itself be- 
tween the upper and lower 
incisors and forcing the upper 
incisors still farther forward, 
and the wrong tension of the muscles of the upper lip over the 
canine region. 

The elongation of the incisors from non-support of the lower in- 
cisors follows, and the articular motions of the mandible still farther 
extends the protrusion of the upper incisors. A very similar inharmony 




Fig. 367. 



534 



ORTHODONTIA. 



of occlusion of the anterior teeth and disfigurement of facial lines is 
often seen in the protrusions of Class I. See Figs. 479 and 481. 

It is believed that the distal position of the lower arch in cases of this 
class is caused primarily by the lack of lateral development of the upper 

arch, because expansion of 
the upper arch in the early 
treatment of these cases 
often restores the normal 
relations of occlusion in the 
molar region, by allowing 
a farther forward position 
of the mandible without 
cusp interference. The 
author has had a great 
many cases in which reten- 
tion of this position was 
unnecessary after the teeth 
of the mandible had once 
been allowed to assume a 
through expansion of the 




Fig. 368. 
relation with the upper arch 



normal 
latter. 

Figs. 367 and 368 exhibit two cases of malocclusion, belonging to Class 
I and II, Div. 2 respectively, both of which are associated with mouth- 
breathing, yet presenting very different objective symptoms, and 
necessitating essentially differ- 
ent methods of treatment in 
the restoration of harmonious 
occlusal relations. 

It is of interest to note the 
variation of the inharmony in 
the forms of the two upper 
arches of these cases from the 
occlusal view in Figs. 369 and 
370, the former being high and 
narrow, with inlocked laterals, 
and the latter comparatively 
low, and much broader, with 
outstanding cuspids. 

The high and narrow arch, however is most frequently associated 
with mouth-breathing, varying in height and width somewhat accord- 
ing to the extent of the respiratory insufficiency and lack of develop- 




Fig. 369. 



ETIOLOGY. 



535 



ment of nasal cavities and adjoining structures, as well as in the pecul- 
iar relations of occlusion which may exist in each case. 

The lingual occlusion of the upper molars and bicuspids in Fig. 367 
produces an arrested development of the upper arch which cannot be 




Fig. 370. 



rectified until the labial occlusion of these teeth is restored through 
treatment. 

Figs. 371 and 372 represent a mouth-breather at the ages of six months 
and seven years respectively, and it will be noted that the open and 





Fig. 371. 



Fig. 372. 



drooping mouth and other symptoms are plainly noticeable in both 
pictures, showing that the mouth-breathing was of early origin, and 
had persisted and become more aggravated in its symptoms as the 
child grew older. 



53 6 



ORTHODONTIA. 



The casts of the child's teeth in occlusion in Fig. 373 exhibit a 
malocclusion of Class II, Div. 1 (Angle). Both arches are contracted 
and undeveloped, there being insufficient space for the eruption of the 
upper and lower lateral incisors, and in addition, the lack of anterior 
occlusion. 

Mouth-breathing is usually called a habit, but in reality is a neces- 
sity, because of the inability to breathe properly through the nose, there 
being some impediment in the nasal tract which will not allow the air to 
pass by it. 

Obstructions to Nasal Breathing. — Among the various obstruc- 
tions to nasal breathing may be mentioned deflection of the nasal 
septum, hypertrophied tonsils, and turbinate bones, adenoids, and the 
diseased conditions resulting from syphilis, tumors, polypi, and cysts. 




Fig. 373. 



"If the nasal and post-nasal passages are unobstructed, every 
inspiration empties the ethmoid veins and through them the longit- 
udinal sinus and cavernous plexus. When there is obstruction to 
nasal respiration, the circulation at the base of the skull is interfered 
with, and a long train of ills brought which interferes very greatly with 
the health of the individual. In the first place, the quantity of air 
aspirated through the mouth in a case of nasal obstruction is not 
equal to that of normal nasal respiration, and the system sutlers from 
lack of sufficient oxygenation" (Grunwald). 

Ziem's experiments in producing nasal stenosis in young animals 
by occluding one-half of the nose artificially, with the result of the 
asymmetrical development of the two sides of the nose and adjacent 
bony tissues, the obstructed half being arrested in development, as 
well as the contiguous tissues on that side of the face, are worthy of 



ETIOLOGY. 



537 



note as proof of the correctness of the theory that nasal obstruction 
is causative of arrest of development in the human head and face. 

It is important that the diagnosis of the obstruction of the air 
passages should be made as early as possible after its incipiency, so 
that by proper treatment and operation, if necessary, normal develop- 
ment may not be more seriously interfered with, and the health of 
the child seriously impaired. 

There are so many local symptoms of this abnormal condition that 
even the novice ought to be able to diagnose it. 

Vocalization is impaired, especially in the pronunciation of the 




Fig. 374- 



letters m and n, which, in the muffled voice of the mouth-breathers 
sound like b. 

A persistent catarrhal condition, often mistaken by parents for 
an ordinary cold, together with an unusual dryness of the pharyngeal 
mucous membrane, and the continued drooping open of the mouth, 
ought to give warning of the beginning of serious nasal obstruction. 

If allowed to continue, deficient nasal respiration may be causa- 
tive of arrested development, not only in the face and head, but in other 
parts of the body, insufficient oxygenation causing anemic conditions 
of the general system, the dulling of the mental faculties, and a favor- 
able opportunity for the inception of infectious diseases, especially 
tuberculosis. 



538 



ORTHODONTIA. 




Deviation of Nasal Septum. — In the normal subject the nasal 
septum occupies a position in the nasal cavity dividing one-half of the 
nose from the other. 

Slight deviations are frequently seen in people who are not troubled 
with nasal stenosis to any degree, but where there is an extensive devia- 
tion from the median line, oc- 
clusion of the side toward which 
the deviation takes place occurs, 
with consequent deficient nasal 
and enforced mouth-breathing. 
Fig. 346 illustrates a skull sec- 
tion (from Cryer) in which the 
nasal septum is in its normal 
median position, the choanae on 
each side being equal in size. 

Fig. 374 portrays a marked 
deviation of the septum to the 
right. The choana on the side 
toward which the septum is de- 
flected is very much smaller than 
the other, and must have been 
almost completely occluded dur- 
ing life, and there is every reason to believe that the subject was a 
mouth-breather. 

Operations for the straightening or partial removal of the septum 
when deflected, are of common occurrence, and are usually followed 
by immediate relief to the deficient nasal respiration. 

Hypertrophy of Faucial Tonsil. — Another cause of nasal 
stenosis is the hypertrophy of the faucial tonsils, and from the 
frequency with which operations for their removal are 
performed, their diseased condition and obstruction to 
nasal breathing cannot be judged uncommon. 

The faucial tonsils are frequently the seat of infec- 
tion and disease because of the hypertrophied condition 
and improper performance of function. 

The large globular masses of tissue in Fig. 375 are the faucial 
tonsils removed from the throat of a two year old child, and are so 
hypertrophied that they are considerably larger than the same glands 
in the adult. 

Hypertrophy of the turbinate bones, especially the inferior, 
is not an infrequent cause of nasal stenosis, and consequent mouth- 



Fig. 375- 



Fig. 376. 






ETIOLOGY. 539 

breathing. Fig. 376 exhibits a portion of the inferior turbinate which 
was removed from the nose of one of the author's patients who was 
suffering from partial nasal stenosis. 

Adenoids. — One of the most common causes of mouth-breathing is 
found in the hypertrophy of the pharyngeal, or Luschka's tonsil, which 
is situated in the vault of the naso-pharynx, usually just out of sight 
above the uvula. 

A mass of this enlarged glandular tissue may be seen in Fig. 377, 
being a posterior rhinoscopic view of the naso-pharynx, and it can 
be readily observed that the nasal passages may become completely 
occluded by the downward growth of this tissue. 




Fig. 377. 

Dr. F. Park Lewis has called attention to the possibility of 
impairment of function • of nutritive vessels passing through the 
carotid canal, which bears the carotid artery, the superior cervical 
sympathetic and the lymphatics, through the pressure of adven- 
titious growths in the naso-pharynx upon the tissues which pass 
through the foramen lacerum medium, which is immediately above 
the site occupied by the adenoid tissues, and opening into the 
carotid canal. 

His conclusions are based upon those of Sajous in regard to the 
control of all oxygenation processes in the body through the pituitary 
bodies, which are very closely associated with the nutrient vessels 
passing through the carotid canal. 

Sajous* Theory. — Sajous indicates the significance of these organs 
and their physiological and pathological importance in this connection 



540 



ORTHODONTIA. 



as follows: "It will be apparent that any lesion capable of blocking 
the afferent and efferent impulses that travers it at all times, and 
which represent the aggregate of the organism, inciting and governing 
energy, must necessarily compromise life, or the functions of an organ 
to which the blocked nerves are distributed." 

"The large mortality under chloroform in adenectomy is in all 
probability due to the shock conveyed to the posterior pituitary body 
through the foramen lacerum medium immediately over the lymphatic 
enlargements." 

"It will readily be seen, therefore, that whatever interferes with 




Fig. 378. 



the nutritive functions at the vault of the pharynx may disturb the 
subsequent development of the whole skull and its contents." 

The very close relationship which exists between the tissues of the 
pharynx, and the nutritive vessels of the carotid canal may be seen 
from observation of the position and direction of the more nearly 
vertical of the two probes passing through the skull section in Fig. 378, 
it being passed through the foramen lacerum medium and emerging 
into the space occupied by the pituitary body. The inferior opening 
of the foramen lacerum medium is in the adenoid region, and the 
vessels which enter it are very apt to be impinged upon by hyper- 
trophy of the pharyngeal tonsils, and the nutrient and nerve supply 
to the pituitary bodies cut off enough to materially affect the proper 



ETIOLOGY. 



541 



performance of the functions of these organs, with consequent disturb- 
ance of development of the whole skull and its contents, as well as 
that of the whole organism. 

The horizontal probe in Fig. 378 passes through the optic foramen 
into the space occupied by the pituitary bodies, illustrating the very 
close relationship between the vessels of the eye and the pituitaries, 
and suggesting the probability of visual defects and insufficiencies 
from hypertrophied tissues in the naso-pharynx. 




Fig. 379. 



Removal of Adventitious Growths. — Even granting that these 
theories should not prove to be all that has been claimed for them, it 
would hardly seem to be necessary to argue the necessity of early treat- 
ment of malocclusion and the removal of all nasal and post-nasal 
obstructions to nasal respiration, thus insuring development before the 
period of normal and rapid growth has passed, together with the 
opportunity of greatest benefit to the patient. 

Irreparable damage may be done by the neglect to observe the 
early symptoms of nasal obstruction, and the immediate placing of 
the patient in the hands of a competent rhinologist for operative 
treatment. 

Deformed arches of teeth and disfigured features become confirmed 



54- 1 



ORTHODONTIA. 



in their abnormality after a long period of abnormal development, and 
neither the local tissues nor the general system will respond to remedial 
measures to anything like the degree that they would had they been 
operated upon at an early age. 

Fig. 379 represents a very characteristic expression of a mouth- 
breather of four years of age, who later, at the age of seven, was 
brought to the author for treatment of malocclusion. 

The segregated mass of tonsillar adenoid tissue shown in Fig. 380 
was removed from the naso-pharynx of this patient by a rhinologist, 
before treatment of the malocclusion was instituted. 




Fig. 380 



A diagnosis of the malocclusion revealed the mesial occlusion of 
the lower arch of teeth as seen in Fig. 526, and the restoration of the 
normal mesio-distal relations of the arches resulted in the change of 
occlusion noted in Fig. 527, the operation being performed entirely 
upon the deciduous teeth. The change in the appearance of the 
boy from the mouth-breather in Fig. 381, with his features all distorted 
in his efforts to close the mouth, to the calm, peaceful facial lines after 
the removal of these obstructing growths and correction of the mal- 
occlusion, in Fig. 382, indicates the advantage gained by early operat- 
ing in this class of cases. 

The development of this face along normal lines of growth is 
now assured and there is nothing left undone to insure the very best 
results in the restoration of facial harmony and normal respiration, 



ETIOLOGY. 



543 



and consequently the attainment of proper physical development 
which in this case, was already deficient. 

Mechanical assistance in holding the mouth closed after removal 
of nasal obstructions and correction of malocclusion, such as the 
wearing of head bandages and mouth plasters, is beneficial in the 
treatment. 

Irreparable damage is done by the oft repeated advice to "wait 
until the permanent teeth are all erupted before beginning operations 
for correction of malocclusion," and even greater damage may be done 
by the neglect to observe the early symptoms of nasal obstruction, 





Fig. 381. 



Fig. 382. 



and the immediate placing of the patient in the hands of a competent 
rhinologist for operative treatment. 

Deformed arches of teeth and disfigured features become confirmed 
in their abnormality after a long period of abnormal development, 
and neither the local tissues nor the general system will respond to 
remedial measures to anything like the degree that they would had 
they been operated on at an early stage. 

The head contains the portals of the human body, and it should be 
the duty of the orthodontist to guard against any ill effects to the 
health through the neglect of the oral cavity, its teeth, and related 
structures of nose and throat. Mouth-breathing, especially, should be 
prevented by such means as are at our command, with the aid of the 
rhinologist, and the correction of such resulting defects in occlusion 



544 ORTHODONTIA. 

of the teeth and inharmony of the facial lines as may be necessary at 
the time the case presents with the symptoms of nasal stenosis. 

Local Factors in Malocclusion. — Among the local causes of 
malocclusion of the teeth may be mentioned prolonged retention of 
deciduous teeth, premature loss of deciduous teeth, loss of permanent 
teeth, thumb-sucking and lip-biting, supernumeraries, and abnormal 
frenum labium. 

Prolonged Retention of Deciduous Teeth.— The retention of a 
deciduous rooth beyond the time for its natural loss through absorption 
of its roots forms a mechanical barrier to the normal eruption of its 
permanent successor, which is deflected labially/buccally, or lingually. 
The permanent central incisors in Fig. 383 were deflected lingually 




Fig. 383- 

through the prolonged retention of the deciduous centrals, the roots 
of which did not absorb. 

As soon as these conditions are observed, the deciduous teeth which 
have been retained beyond the time for their natural loss should be 
extracted, and the permanent teeth which have been deflected assisted 
into normal positions in the arch. 

Premature Loss of Deciduous Teeth. — One of the prolific 
secondary causes of malocclusion and lack of arch development is 
the premature loss of the deciduous teeth, especially of the incisors 
and cuspids. That the mechanical influence of the deciduous teeth 
in assisting in the development of the arch is a necessity up to the time 
when natural absorption of the roots of the deciduous teeth should 
take place, one has only to observe the contraction of the spaces 
occupied by prematurely lost deciduous teeth to readily understand. 

An illustration of the retarded development caused by the pre- 



ETIOLOGY. 545 

mature extraction of all deciduous teeth at eight years of age may be 
seen in Fig. 384. It is easy to prognosticate a serious malocclusion upon 
the eruption of the remaining permanent teeth. 

The loss of the approximal surfaces of the deciduous teeth by 
caries is also causative of lack of arch development through the loss 
of the mechanical influence of the deciduous teeth in their entire 
mesio-distal diameters, and such carious conditions should be observed 
in their earliest stages and fillings inserted to restore full approximal 
contour. 

The loss of permanent teeth through extraction or disease, by destroy- 
ing arch integrity is another frequent cause of malocclusion, which 
is considered under the heading, "The Problem of Extraction." 




Fig. 384. 

Thumb-sucking and Lip-biting. — The habits of thumb-sucking, 
lip and tongue biting are responsible for the inception of some maloc- 
clusions, and for the aggravation of a very great many cases, with 
other primary causative factors. 

Thumb-sucking is not as frequent a causative factor in malocclusion 
as is generally supposed, but that it does affect the development of 
the arch is certain. Usually, but one side of the mouth is affected, 
according as to which thumb is used, although it is not uncommon to 
find that the thumb is held in the center of the mouth, protruding the 
upper central incisors. When the thumb is held on either side of the 
center, the upper incisors on the side in which the habit is induced 
are protruded. 

In Class I and II cases in which the upper incisors are protruded, 
the habit of biting the lower lip has a pernicious influence in increasing 
the extent of the malocclusion, and in some cases is believed to be the 
initial cause of the abnormal occlusal relations. 

The inculcation of a similar habit with the tongue is productive 
35 



54^ 



ORTHODONTIA. 



of more or less deviations from the normal in occlusal relations, and 
the observance of any of these habits by the parent or dentist should 
be followed by efforts on their part to overcome the habit and the 
damage already done. 

Prevention of Thumb-sucking. — A very practical method of 




Fig. 385. 

preventing a child from sucking the thumb is to enclose its hands in 
polished aluminum balls, such as is shown in Fig. 385, attached by a 
sleeve to the child's arm, and worn as much of the time as possible, 
especially at night, until the habit is broken up. Such a device is on 
the market by the name of Hand-I-Hold Babe Mit.* 

The wearing of mits of this kind will enable the child to use its 




Fig. 386. 

arms, yet at the same time, prevent the possibility of getting the 
fingers or thumbs into the mouth, and is much more humane than 
tying the arms. The balls are ventilated by several small holes, and 
the sleeve and ball may be easily sterilized by boiling. 

Supernumeraries. — Supernumerary teeth are occasionally found 

* Manufactured by the R. M. Clarke Co., Boston. Mass 



DIAGNOSIS. 547 

in the mouth, and are usually of the peg-shaped variety shown in Fig. 
386, although sometimes resembling an adjacent normally developed 
tooth to such an extent that an X-ray diagnosis is necessary to differ- 
entiate between them. 

Their removal is usually indicated, and the restoration to normal 
position of the teeth which have been forced out of their alignment. 

Abnormal Frenum Labium. — The abnormal attachment of the 
frenum labium sometimes causes the separation of the upper central 
incisors, acting as a rubber cushion to force these two teeth apart. 
Cases of this character are somewhat difficult to treat, unless operative 
measures are resorted to for the partial removal of the ligament, so 
as to render it incapable of exerting lateral pressure. This operation 
is described under operative technique. 

IV. DIAGNOSIS. 

General Considerations. — A thorough diagnosis of any case of 
malocclusion should include the observance of every pathological in- 
dication in the oral cavity and adjacent parts of the head and face, 
for only with a full understanding of the variations from normal con- 
ditions is it possible to produce the best results in treatment. 

If the deciduous teeth are present in part or whole, it should 
be noted whether they occupy their full mesio-distal space, and 
are assisting by their presence in the development of the arches. 
Their premature loss is usually indicated by a closing up of part 
or all of the space which they originally occupied, and indicates 
non-development. 

A primary examination of the permanent denture should first deal 
directly with each individual arch, noting the absence of teeth, and 
their effect upon each arch, tracing minutely the changes incident to 
their removal in the contraction of the arch, and secondarily the 
effect upon the occlusion and articulation. 

Accurate plaster models should be made and the normal sizes of 
the arches determined by a method of arch pre-determination to be 
described. 

The case should be classified, and the etiological characteristics 
present carefully observed. 

The variation of the facial lines from harmony should be studied 
in relation to the occlusion, and an inquiry into the history and habits 
should, by exclusion, remove any doubt as to their signification in 
the case. 



548 ORTHODONTIA. 

Mouth-breathing, especially, will be readily detected from an 
observance of the distortion of the face and mouth peculiar to this 
pathological condition. The presence of enlarged tonsils may be 
easily seen with the tongue depressed slightly, and adenoids may be 
felt with the index finger carefully and quickly inserted into the throat 
above the uvulae. The examination for adenoids and deflected septa 
and other nasal obstructions should be made by the rhinologist as 
soon as there is any suspicious indication of there being such path- 
ological conditions present in the case. 

The patient's general health should be inquired into, and the 
advisability of beginning or deferring treatment considered. 

The principles of diagnosis in orthodontia are necessarily based 
upon anatomical variation in development of the maxillary and dental 
arches, including the variation from the normal in the occlusal relations 
of the teeth, with especial reference to etiological considerations, de- 
scribed in the preceding chapter. 

As any diagnostic interpretation is only of value insofar as it is of 
use in prognosis, it will be recognized that the greatest benefits to be 
secured from treatment can only be assured by an intelligent percep- 
tion of all the etiological and pathological factors involved in the 
case, no one of which is so obscure as not to be considered. 

The history of the patient, with carefully detailed subjective and 
objective symptoms of pathological significance should be a matter of 
careful detail and should be recorded systemically for future reference 
in the treatment of the case. 

Classification of Malocclusion. —In contrast to the chaotic 
designation of deformities of the dental arches in use a decade ago, it 
has remained for Dr. E. H. Angle to point out to the profession the 
natural divisions and subdivisions into which malocclusion is divided, 
and upon which the scientific treatment of malocclusion is founded, 
the successful results of which are in evidence in the practices of the' 
specialists working along these lines throughout the world. 

The Angle classification of malocclusion is based upon the mesio- 
distal variation of the dental arches from the harmonious relationship 
of normal occlusion, three distinct classes being represented, and an 
occasionally found fourth class. 

Class I. — To the first class belong those cases of malocclusion 
which are characterized by normal mesio-distal relations of the dental 
arches, with contracted and undeveloped maxillary arches, especially 
in the anterior portion, in which the teeth often assume varied forms 
of individual malocclusion, and often simulating in this anterior region, 



DIAGNOSIS. 549 

the peculiarities of Classes II and III, both in the occlusion and facial 
deformity. 

Class II. — In the second class of malocclusion are placed all those 
cases in which the lower dental arch is distal to the upper on one or 
both lateral halves, having two divisions of bilateral distal occlusion, the 
first division being characterized by protruding upper incisors, usually 
mouth-breathers, and having a subdivision in which the distal occlu- 
sion is confined to one lateral half, the other half being in normal 
mesio-distal relations; the second division having retruded upper in- 
cisors, usually normal breathers, and its subdivision having the distal 
occlusion on one lateral half of the dental arches only. 

The facial profile of a case of the first division of Class II is usu- 
ally diagnostic of the occlusal relations, the upper lip being short, and 
revealing the protruded upper incisors, and the receding chin indicat- 
ing the distal occlusion. As these cases are usually mouth-breathers, 
the characteristic open drooping mouth and peculiar tension of the 
facial muscles is a sure indication of naso-pharyngeal obstruction of 
present or previous date. 

The facial deformity is not so pronounced in the second division, 
the patients usually being normal breathers, the upper lip being 
of proper length, but the features disfigured by the receding chin and 
lower third of the face. 

Class III is characterized by a position of the lower arch which 
is mesial to the upper, with protruding lower incisors, having a division 
in which the mesial occlusion is bilateral and a subdivision in which 
the mesio-distal relation to the upper is normal in one lateral half 
of the lower arch and mesial to normal in the other. 

The facial profile is correspondingly deformed, the chin being 
prominent, the middle third of the face undeveloped, the angle of the 
rami of the mandible being more obtuse than normal, and, in some 
cases of long duration, there being scarcely any discernable angle 
between the point of the chin and the articular ends of the condyles. 

Mouth-breathing is frequently observed in this class, and its ex- 
istence in any case serves to increase the inharmonious lines of the 
already deformed face. 

Class IV. — A very rare class, although found to exist in sufficient 
numbers to be worthy of record, and treatment, is Class IV, in which 
the occlusal relations of the dental arches present the peculiar condi- 
tion of being in distal occlusion upon one lateral half, and in mesial 
occlusion upon the other half of the mouth. 

As diagnostic of these various classes, the variation from the normal 



550 ORTHODONTIA. 

mesio-distal relations is usually best indicated by the relative mesio- 
distal relations of the upper and lower first permanent molars in 
occlusion, since they present a history of the longest lived occlusion 
during the ages in which malocclusion usually presents, and having 
such an important part in the building of the permanent dentition as 
to be appropriately styled "the bulwarks of the dental arches." 

Classification Chart. — In order that the principles upon which 
this classification is based may be the more readily understood, the 
author has arranged the four classes in comprehensive chart form in 
Fig. 387, the right and left lateral halves in occlusion being represented 
in each section, with the line of diagnosis intersecting the occlusion 
of the mesio-buccal cusps of the first permanent molars of each class, 
and illustrating at a glance, the deviation from the normal mesio-distal 
relations of each lateral half in each class, division and subdivision. 

The use of the upper first molar for the purpose of noting mesio- 
distal variation of the lower dental arch presupposes a certain un- 
varying stability or a fixed position of this tooth in relation to the 
maxilla and the adjacent anatomical regions, which might be under- 
stood as being absolute, but such is not the case. 

Cases have been reported in which the upper first molar was mesial 
or distal to its normal position in the arch, although the infrequence of 
these cases and their observance only affects the classification as far 
as certain details of the treatment is concerned, the main points of 
the treatment indicated thereby being essentially unaffected. 

In simple, the indications for treatment as observed in the chart 
are, first, the restoration of normal shape and size of the dental arches 
in each class, second, the restoration of the normal mesio-distal 
relations of the arches in Classes II, III, and IV. 

Notwithstanding the various criticisms which this classification 
has received from a theoretical standpoint, it has been proven beyond 
question to be of greater practical value than a more complicated 
classification in which the minute details of arch malformation and 
facial inharmony are combined. The especial criticism which has 
been made against this classification is in regard to the particular 
relationships of the maxilla and mandible to the internal face in Class 
II and III, the claim being made that cases are found in which in 
Class II, for example, the upper arch of the maxilla is protruded in 
relation to the internal skull, and the mandible retruded from a normal 
relationship to the internal skull, and vice versa, in Class III. Very 
few records have been found of this class of cases, and their paucity 
only strengthens the classification of Dr. Angle, since they represent 



DIAGNOSIS. 551 

individual characteristics of forces operating in malocclusion which 
have to be taken into account in any class, and which require only 
mention in a context in the same manner that open-bite malocclusions 
are noted, their treatment following along the same lines as the class 
they simulate or exaggerate, aided by the individual skill and judg- 
ment of the operator. 

Infra-occlusion. — Infra-occlusion, or lack of occlusion of the 
teeth, is a condition of abnormal development occurring in several 
different forms, and more or less common to all classes of malocclusion 
requiring special description in a classification based upon the mesio- 
distal variations only of malocclusion. 

Varying as it does from the slight infra-occlusion of one or two 
teeth to complex cases in which the entire dental apparatus is involved, 
its diagnosis, in any extensive form, places the presenting case in the 
class of the most difficult to treat. 

Associated as it usually is, with mouth-breathing, the functions of 
normal breathing must be restored before treatment is successful, as 
it is believed that mouth- breathing is the greatest causative factor in 
its production. 

Add to this the overdevelopment of one region and the under- 
development of another part in the same maxillary arch, and the 
extent of the abnormal conditions present may be understood. 

Variations of Infra-occlusion. — Infra-occlusion occurs in several 
forms, best described by the designation of the region in which it is 
observed, as infra-occlusion of incisors, cuspids and bicuspids, infra- 
occlusion of bicuspids and molars, and full bimaxillary infra-occlusion. 

Infra-occlusion of Incisors, Cuspids, and Bicuspids. — By 
far the most common form of infra-occlusion is observed in the 
lack of occlusion of the in'cisors, cuspids, and bicuspids, sometimes 
including the first and second permanent molars, varying usually 
with the extent of the mouth-breathing. 

It is especially characterized by lack of development of the pre- 
maxillary portion of the arches, and oftentimes overdevelopment of 
the posterior portion of the same arches. 

Fig. 388 illustrates an extensive case of infra-occlusion extending 
distally as far as the molar region. 

Bilateral Infra-occlusion of Bicuspids and Molars. — Exten- 
sive infra-occlusions involving the molars and bicuspids on one or both 
sides, may occur in any of the various classes of malocclusion. Fig. 469 
represents acase of bilateral infra-occlusion of the molars and bicuspids, 
and in its mesio-distal relations, it may be classified as a Class I case. 



55 2 



DIAGNOSIS. 




CLASS I 





CLASS II 
DIV. 1 





CLASS II 

DIV. 1. 
SUB -DIV. 





CLASS 
DIV. 2. 




\, LINE OF DIAGNOSIS. / 

Fig. 387. — Diagnostic chart of the mesio-distal variations in malocclusion. 
Based upon theAngle classification. 



ORTHODONTIA. 



553 




CLASS II 

DIV. 2. 

SUB-DIV. 





CLASS III 
DIV. 





CLASS 
DIV. 
SUB-DIV 




CLASS IV 





\ 



LINE OF DIAGNOSIS. 



/ 



Fig. 387. — Diagnostic chart of the mesio-distal variations in malocclusion. 
Based upon the Angle classification. 



554 ORTHODONTIA. 

Unilateral Infra-occlusion oj molars and bicuspids is a condition 
more commonly observed as the result of arch mutilation through 
extraction especially of the first permanent molars. 

Full Bimaxillary Infra-occlusion. — Another extensive case of 
infra-occlusion, involving all of the teeth of both arches, described by 
Dr. C. S. Case, in the Denial Cosmos, for December, 1905, page 141 1, 
is worthy of especial notice, as requiring special classification. 

As seen in the cast on the right of the cut, Fig. 389, the teeth, 
anteriorly and posteriorly, are very much too short in relation to the 
plane of occlusion, although being comparatively normally related 
mesio-distally, and the arches quite fully developed and of normal 




Fig. 388. 

shape. When the jaws are closed, as in the model on the left of this 
figure, the facial appearance is that of an edentulous mouth, with its 
lines of senility caused by the approximation of the nose and chin, and 
the unnatural fullness of the lips and cheeks, as illustrated in the face 
mask on the left of the cut. The. model and face mask on the right, 
the normal pose of the profile, was obtained by placing a piece of 
modeling compound between the teeth, and the distance between the 
arches of teeth adjusted until the profile appeared normal. 

Arch Predetermination. — An accurate conception of the normal 
size and shape of the dental arches in malocclusion is no longer a 
matter of guesswork since the mechanically and anatomically recon- 
structed arch has been made a possibility by the application of the 
laws of Bonwill in the synthetic reproduction of the normal arch for 



DIAGNOSIS. 555 

any given case, as worked out geometrically by Dr. C. A. Hawlej 
who by a reversal of the method of triangle construction of Bonwill, 
has succeeded in predetermining the size of the arch by constructing a 
triangle from a primary measurement of the arc of the centrals, laterals 
and cuspids. 

A scientific determination of the normal arch in any case of mal- 
occlusion not only removes any doubt as to the extent of arch expan- 
sion in treatment, but provides for the establishment of the normal 
function of articulation, which is most important in mastication, and 
preservation of arch integrity, which the construction from an equi- 




Fig. 389. 

lateral triangle, aided by the relationship of length of cusps to depth 
of overbite, and the compensating curves from cuspid to molars, 
affords by the harmonious working of these laws. 

Quoting from Dr. Hawley's article on arch determination, the con- 
struction of the triangles and reproduction of the normal arch for any 
given case is as follows: 

Dr. Bonwill's Diagram.— "In Fig. 390, we have Dr. Bonwill's 
geometrical figure, an equilateral triangle, AFG, inscribed within a 
circle, its base FG representing the distance between the condyles, 
which varies in the living subject from three to five inches. According 
to his plan, in artificial dentures, the teeth are arranged with the 



550 ORTHODONTIA. 

cuspids and incisors in the arc of the circle AJCH, the size of which 
varies according to the size of the teeth selected for the case, and this 
selection is left to the judgment of the operator." 

Dr. Hawley's Diagram. — "In order to use this principle in ortho- 
dontia, where we have the size of the teeth given us, and from their 
widths the diameter of the circle AJCH, we must reverse the order of 
procedure and find a connecting relation between this circle and the 
equilateral triangle AFG, or the circle within which it is inscribed. 



A' i?" 



1 

Fig. 390. 

This connection is not described in Dr. BonwilPs writings so far as 
I have been able to find. It is found in the triangle EDC, constructed 
with its apex at the point C, on the diameter of the circle AJCH, and 
its base tangent to the same circle at A, the sides passing through the 
points J and H, located on the circle by the distance of the radius 
from A." 

"In application, to construct the diagram, we take the radius of 
the circle AJCH from the combined widths of the central, lateral, 
and cuspid teeth shown at AB. With this radius AB, upon the line 



DIAGNOSIS. 



557 



AC, which becomes the extended diameter of the circle, draw the 
circle AJCH, and with the point of the compass at A, mark off the 
radius upon the circumference at H and J. We have here the arc 
of the circle upon which the six front teeth are to be arranged, but 
know nothing of the size of the triangle AFG." 

"From C draw the lines CE and CD, through H and J, extending 
them indefinitely and draw a tangent to the circle A, cutting these lines 
at E and D, and forming an equilateral triangle ECD. Take one side 
of this triangle as a radius, and with one point of the compass at A, 
and the other upon the extension of the diameter at I, describe the 
large triangle AFG. Then draw the lines FJ and GH, and we have 
the desired diagram or arch upon which we may measure off the 
teeth with the width as found in the mouth." 




Fig. 39: 



Fig. 391 represents the upper arch of teeth drawn in position on 
the predetermined arch, after their mesio-distal diameters had been 
measured off from each side of the median line. 

The Simplified Method. — Although this gives a very graphic idea 
of the normal arch for a given case, Dr. Hawley's second method is 
more practical because of its not requiring special artistic ability in 
drawing, and but a short time is needed to complete it. 

The line drawing of the predetermined arch is transferred to a 
piece of transparent celluloid, a suggestion of Dr. L. P. Bethel's, and 
by placing this in position over the occlusal surfaces of the teeth of 
an upper or lower cast of the case before treatment, the extent of ex- 
pansion, and change in the shape of the arch, laterally and anteriorly, 
is very plainly indicated. 



558 



ORTHODONTIA. 



Fig. 392 represents a case of malocclusion of Class II, Div. 1, (Angle) 
in which it was desired to determine the normal size and shape the 
arches of teeth should assume after treatment. 

The superimposed diagrams are seen in Fig. 393 upon the upper 
and lower casts of the case before treatment and indicate considerable 
widening and shortening of the upper arch, and but very little ex- 




Fig. 392. 



pansion of the lower, the apparent disparity being explained by the 
fact that the lower arch is very nearly its normal size, and only requir- 
ing the forward shifting of its teeth to harmonize in occlusion with 
the upper arch, the distal position having been assumed because of 
the narrowing of the upper arch. 

Fig. 394 illustrates the occlusal views of the finished case with 



DIAGNOSIS. 



559 



the diagrams in position, and the new "line of occlusion" (Angle) 
coinciding with the predetermined arch. 

The front and side view of the completed case in Fig. 395, in har- 
monious relations of occlusion, testify to the accuracy and correctness 
of the method, and to its value in diagnosis, prognosis and treatment. 
Comparative arch and tooth measurements in the mouth and on 




Fig. 393. 

the diagram in the progress of a case, will serve as a constant guide 
to the attainment of the predetermined arch. These measurements 
are made with a scale graduated in hundredths of an inch, and one 
with specially fine points has been adapted by Dr. Hawley for the 
purpose. (See Fig. 396.) 

Table of Average Measurements. — So far, in the use of this 




Fig. 394. 



method, the measurements have been taken from arches in which the 
full complement of permanent teeth is present, but, by means of a 
system of comparative tooth measurements in a large number of cases 
in which the permanent teeth are all present, Dr. Hawley has succeeded 
in formulating a table of average measurements, especially of the cen- 



560 



ORTHODONTIA. 



trals, laterals and cuspids, so that by the measurement of a single 
central incisor in a case in which the permanent centrals and first 
molars were the only teeth erupted of the permanent dentition, the 
width of the permanent lateral and cuspid to be erupted later may be 
quite accurately gauged, and consequently the arc of the anterior teeth 
from which the entire permanent arch is determined. 

Quoting from Dr. Hawley, the method of making these tables and 




Fig. 395. 



their applicability may be more clearly shown as follows: "Now, 
if the teeth were found in the mouth in the same proportion in respect 
to their greatest and least width, that is, if with a .31 central, we would 
find a .19 lateral, a .27 cuspid, a .27 first bicuspid, a .23 second bicuspid, 
and a .35 molar, and so on with each size of central, we could make 
out the radius of each size central, and from these draw proportional 
diagrams. But such is not by any means the case, for, with a .31 



DIAGNOSIS. 



56l 



central, we often, in fact usually, find a lateral .26 or .27, and the 
cuspid may be quite well up in the scale, or we may have a central 
and lateral in good proportion and the cuspids much larger." 

"In order to discover the nature of this variation, I selected from 
the 100 measurements all the cases of each width of central, and made 
of each of them a table." 

"The number of cases of each size central was .31, fifteen, .32, 




Fig. 396. 

seven, .33, sixteen, .34, sixteen, .35, nine, .36, fourteen, .37, thirteen, 
.38, five, and .39, two. 

Collecting each of these sets, nine tables were made, each repre- 
senting the variation in width of the laterals, cuspids, bicuspids, and 
first molars in arches in which the central incisors were all of the 
same width, of which the table below of the .35 central is an example: 



ENTRAL 


Lateral 


Cuspid ist Bic 2d 


Bic 


ist Molar 


■35 


.24 


•3 1 


27 


27 


.41 


■35 


.28 


•3 1 


29 


30 


.41 


•35 


•25 


•30 


2 5 


25 


•42 


•35 


.28 


•3 1 


28 


27 


.42 


•35 


.27 


•33 


29 


29 


•44 


■35 


.24 


•3° 


30 


28 


.41 


■35 


.28 


■33 


29 


26 


.40 


•35 


.26 


•30 


27 


27 


•43 


•35 


.27 


•3 2 


27 


27 


.41 


Average : 












•35 


.27 


•3 1 


28 


27 


.42 



The average measurements of the nine tables were then computed, 
forming an average table with centrals of varying width from .31 to 
36 



562 ORTHODONTIA. 

.39, and the average widths of the other teeth, as in the following 
table: 

Cext'l Lateral Cuspid ist Bic 2D Bic ist Molar Radius Corrected radius 



31 


.26 


.29 


.26 


.26 


•39 


.86 


.86 


32 


.26 


•30 


.27 


.26 


.40 


.88 


.88 


33 


.27 


•30 


.28 


.27 


.41 


.89 


.90 


34 


.28 


•30 


.28 


.28 


.42 


.92 


.92 


35 


.27 


•3 1 


.28 


.27 


.42 


•93 


•94 


36 


.28 


•3 2 


.28 


.28 


.42 


.96 


.96 


37 


28 


•32 


•30 


.29 


.42 


•97 


.98 


38 


.28 


•34 


•3° 


.29 


.44 


100 


100 


39 


•3 1 


•34 


•3i 


.29 


•44 


104 


102 



The combined widths of the central, lateral-and cuspid in each one 
of the nine tables, represents the radius that may be used for the 
predetermination of the arch. 

The Corrected Radius. — A corrected radius at the extreme right 
of the table is based upon a uniform variation of .02 of an inch from 
.86 to .T02. 

Quoting again from Dr. Hawley: "Now, taking these corrected 
radii, we will get an arch for each width of central, and I will propose 
these as a basis of diagnosis, study and treatment of cases where only 
part of the teeth are erupted, or under the age of twelve." 

"Or using the radius in hundredths of an inch for comparison, 
they may be used as a guide for all cases, for where we can measure 
all the teeth, we have only to select the diagram with the correct radius, 
arid measure in the teeth. Remembering that these arches are only 
averages, and smaller or larger teeth will constantly occur in con- 
nection with the particular central, is there any indication by which 
we can judge in which direction this variation will occur, i. e., toward 
smaller or larger teeth ? I think we have this in the first molar, and 
this tooth is always present at the time of eruption of the central 
incisor. As the first molar varies up or down from the average width, 
I believe the rest of the teeth will vary. For instance, we will sup- 
pose we have a case in which the central incisor is .34 and the first 
molar is .42. If I had a second case with the same size central, but 
with the first molar .44, I would presume that the lateral and cuspid, 
and all the rest of the teeth would be likely to be large, and would 
select the next larger arch. In this way I think we have the key to a 
fairly accurate judgment of the future denture." 

"In making up these averages, I have tried to err, if at all, on the 
side of the larger arch, believing if we do get the arch slightly larger 
than the teeth will fill, if it is properly shaped, and the teeth are placed 
in normal occlusion, as the excess will, at the worst, be only a few 



DIAGNOSIS. 563 

hundreths of an inch, the pressure of the checks and lips, the influence 
of the occlusal planes and the pressure forward of the second molar 
in eruption will close the spaces." 

Illustrations of Practical Cases. — "In illustration of my use of 
these arches, let us take the case of a child eight years of age, Fig. 
397. We have here erupted of the permanent upper teeth, only the 
centrals and first molars, and in the lower, the centrals, laterals, and 
first molars. All of the lower deciduous molars have been extracted, 
as well as the lower first deciduous molars. The arches are conse- 
quently contracted, especially the upper, in which the centrals are in 




Fig. 397. 

lingual occlusion. The centrals are .7,1, wide and the molars .37, 
while the average molar for that diagram is .41. As the molar is 
small, I judge we are likely to find small laterals and possibly small 
bicuspids, as these are the teeth that vary most, so I would select no 
larger arch than that for .33. 

"Fig. 398 shows the development that will be necessary." 
"Similar tables were made for the lower teeth, and the result makes 
it evident that the uniformity of lower arches, drawn from the measure- 
ments of the lower incisors and cuspids, is not to be depended upon. 
While the lower bicuspids and molars are fairly uniform in their 
relation to the upper, within the same mouth, the incisors and cuspids 
are not. This lack of uniformity is probably compensated for in the 
inclination of the teeth and the overbite I wish to advise that 



5O4 ORTHODONTIA. 

instead of drawing the lower arch from measurements of the lower 
teeth, .... the radius for the lower be taken from .13 to .23 of an 
inch shorter than the upper, depending within this variation on the size 




Fig. 398. 

of the teeth or the distance from the line of occlusion to the crest of the 
buccal cusps." * 

"Fears have been expressed that, in bringing into orthodontia 
a mathematically and geometrically calculated plan, we would restrict 




Fig. 399. 

or eliminate the feature of artistic judgment, and that the method 
leaves' no room for the exercise of judgment in changing the form 
of the arch to satisfy the requirements of the various types. These 

* For the sake of convenience, accurately drawn charts on transparent celluloid of the 
upper and lower arches, with radii of varying widths from .86 to 1.04 in the upper, and 
.70 to .90 in the lower, have been prepared and placed in the depots. 



DIAGNOSIS. 



565 




Fig. 400. 



fears or objections have been due to misconception of the elasticity 

of the method in its application In so far as hampering, 

in any way, the use of judgment in the 
art requirements of orthodontia, this 
method lays down the most valuable 
principles, and forms the most important 
basis upon which artistic results in ortho- 
dontia must be accomplished; and in- 
stead of restricting the variation of the 
arch to correspond to different types, it 
forms the only safe guide for procedure 
in such variation." 

"By restoring normal occlusion, and 
a form of arch in harmony with the size of the teeth, that will admit 
the natural movement of the mandible, we will thus, so far as the 

mechanism is concerned, obtain the 
natural development of the denture. 
And in retention, we will guard against 
any final retrogressive changes that might 
take place, by conforming the arch to 
the natural mechanical forces of articu- 
lation." 

The Line of Occlusion.— Until the 
pre-determination of the arch became a 
possibility, the "line of occlusion" de- 
fined by Angle "as the line of greatest 
normal occlusal contact," seemed to answer the purpose of a fixed, 
though imaginary line of the normal arch from which to note devia- 
tions of individual teeth from the normal 
line of the arch, such as would be inter- 
preted from "an incisor in lingual oc- 
clusion," etc. 

Dr. Angle's later definition of this 
line "as being the line with which, in 
form and position according to type, 
the teeth must be in harmony if in 
normal occlusion," is very comprehen- 
sive as to its characteristics, except as to 
the determination of this line in a case of 

malocclusion, where it should be of the most practical value in noting 
deviations from the normal lines of the arches to have a somewhat 




Fig. 401. 




Fig. 402. 



«:66 



ORTHODONTIA. 



accurate idea of the location of this line, as inaccuracy in this respect 
would lead to much confusion. 

The pre-determined arch line, not only accurately locates the 
proper "line of occlusion," but enables one to more exactly designate 
malpositions of the teeth in relation to it. 

It is true that the line of the pre-determined arch is not strictly 
conformative to type, but this is unessential, since the typal form of 
the arches is best produced through the attainment of the proper 
working of the mechanics of the laws of articulation from which the 
line of the pre-determined arch is derived. 




Fig. 403- 



Roentgen Rays. — The use of the Roentgen rays has been of ines- 
timable value to the orthodontist, in enabling him to pre-determine 
the location of unerupted teeth, if present, as well as the shapes of the 
roots of the teeth and their angles of inclination, diseased areas, etc. 

It is properly considered under diagnosis, for with such fore- 
knowledge of the anatomical defects, if any, that the radiograph shows, 
the operator is able to progress with any doubtful case without delay, 
or the possibility of a mistake in treatment due to lack of previous 
knowledge of the exact conditions present. 

Not infrequently, is the orthodontist called upon to diagnose the 
presence or absence of a permanent successor to a deciduous tooth, 




DYNAMICS AND ANCHORAGE. 567 

which the radiograph alone will determine. Such a case is seen in 

Fig- 399- 

The long retention of the deciduous pre-molars on both lateral 
halves of the arch caused some anxiety on the part of the family 
dentist in charge of the case, as he thought they ought to be extracted 
to allow the permanent successors to erupt. 

An X-ray was secured of both lateral halves and the radiographs 
printed (Figs. 400 and 401) proved that the 
second bicuspids were not present, having failed 
to develop, and the deciduous molars retaining 
their full length of roots bid fair to act as effi- 
cient substitutes of the undeveloped bicuspids 
for many years. 

Frequently the cuspid will assume such a 
position in the alveolar process that its proper 
eruption would require surgical interference, as 
in Fig. 402, a radiograph loaned by Dr. C. F 

Edmund Kells. 

Fig. 403 represents the cast of an upper arch in which the cuspid 
is missing on the right side, and the space for its eruption entirely 
closed up. The radiograph of this case, Fig. 404, also by Dr. Kells, 
represents the cuspid in an unerupted stage slightly lingual to its 
position, and the indications for its eruption into position by opening 
up the space for it between the lateral and first bicuspid, are very 
favorable. 

V. DYNAMICS AND ANCHORAGE. 

Force and Resistance. — The relations of force and resistance in 
the application of mechanical apparatus for the correction of mal- 
occlusion, and development of the dental arches, represent the basic 
factors which, in the attainment of desired results in treatment in 
orthodontia, must be considered together in order that a proper utiliza- 
tion and conservation of both may at all times be correctly propor- 
tioned in respect to their requirements in any given case. 

In the consideration of these factors, it must be remembered that 
applied force is active, and to a degree directly opposed to the other 
factor, resistance, which is passive or latent energy, incapable of being 
measured, except by the corresponding degree of active energy neces- 
sary to overcome it in the applied force. 

Resistance, although latent, is nevertheless energy, and the degree 
of one's success in the restoration of harmony in occlusion and facial 



568 ORTHODONTIA. 

lines is to a great extent dependable upon the intelligent use of this inert 
energy, which should always be accurately proportioned to the dynam- 
ical requirements of the necessary tooth movements. 

In regard to the mechanical requirements of anchorage, the limi- 
tations in the quality and quantity of the applied force, because of 
the danger of injuring the living tissues involved, present a striking 
contrast to the application of similar forces in the field of general mechan- 
ics where resistance may be accurately measured and scientifically 
adjusted so that its stability in relation to any dynamical requirements 
may always be positively known. 

In the field of applied mechanics in the arts, "a force acting against 
an unstable resistance is not considered within the limits of practica- 
bility, but in the application of dynamics to living dental and alveolar 
tissues, the mechanical problems in the development of the dental 
arches and correction of malocclusion are not infrequently solved by the 
operation of a force acting from a more or less unstable base. 

It oftens happens that the resistance to tooth movement may be 
located in a single anchor tooth, which is antagonizing the delivery 
of a force in another part of the arch, and is itself being moved at the 
same time in a direction in line with, or at opposing angles to the direc- 
tion of the applied force. 

In other respects, appliances which are used for the development 
of the dental arches and the correction of malocclusion, conform to the 
same laws as other machines used for the transformation of energy. 

Force Producing Appliances. — The force required for tooth move- 
ment which has been found most adaptable to the unfavorable condi- 
tions in the mouth, is embodied in the principles of the spring, the screw, 
the lever, the elasticity of rubber, and the contraction of silk when 
moistened. 

One entire system of correcting malpositions of the teeth is based 
upon the elasticity of the spring in a removable appliance to the ex- 
clusion of all other means of producing force, but lacking the advantage 
of absolute fixation, is not equal to the expansion arch in point of effi- 
ciency, although possessing decided mechanical advantage where its 
use is indicated, in those cases where a greater potential is required 
than is obtainable with the expansion arch. 

The principle of elasticity in the stretching and contraction of the 
rubber band or ligature is also made use of as an important primary 
and auxiliary force, especially in connection with the expansion arch. 

The expansion arch embodies the principles of the spring and a 
double jackscrew in one mechanism with all of the mechanical advant- 



DYNAMICS AND ANCHORAGE. 



569 



ages of both, and when properly adjusted, with its possibilities of fixa- 
tion of anchor clamp bands, offers a combination of essential features 
in an appliance which is not possessed by any other force producing 
mechanisms in orthodontia. 

Dynamics of the Expansion Arch. — A close observation of the 
expansion arch in operation and a knowledge of the tooth movements 
performed by its action as a spring alone, will prove its distribution of 
force to be similar to that of any spring placed on a tension under the 
same mechanical restrictions outside the mouth. 

For example, in Fig. 405, the arch BNE represents an expansion 
arch at the limit of its lateral spring, which has been adjusted for the 
expansion of an arch of teeth. The arch JHI represents the same arch 




Fig. 405. 



after it has been placed in the anchor tubes on molar clamp bands in 
the mouth, and it will be noticed that the center of the bow of the arch 
has bent outward, forming a shorter arc of a circle than before. 

The action of any spring being to return to its original shape, the 
arch JHI will in time return to the shape BNE, the effect upon the 
teeth being to force the anterior teeth backward, through the pressure 
of the expansion arch in this region. At the same time, the lateral 
spring of the arch is expanding in the molar and bicuspid region, and 
it will be seen from the drawing that the expansion at A and M in the 
region of the first bicuspids is almost zero, while at B and E, the 
extreme of arch expansion has taken place. 

The anchor tubes on the molar clamp bands being usually aligned 
about parallel with the buccal cusps, the distal angle of the molar would 



570 ORTHODONTIA. 

travel a greater distance buccally than the mesial corner, or, in other 
words, the molar would be rotated in any case where much expansion 
had taken place. To obviate this, it has been suggested by Dr. J. 
L. Young that the ends of the expansion arch be bent lingually from a 
point directly in front of the nuts on the arch, so that the arch will have 
the appearance of LHK when in position, and in lateral movement will 
tend to counteract the tendency to rotate the molar, for while the ends 
of the arch do not travel in parallel lines buccally, the variation from 
the parallel lines is very slight as seen in the arch CND which repre- 
sents the arch LHK in the extreme limit of expansion. 

Dynamics of the Traction Screw. — The force embodied in the 
traction screw is limited to the positive action of the principle through 
the turning up of a nut against the end of a tube which is securely fas- 
tened to the base of anchorage, the right angled end engaging with a 
short tube attached to a band at the point of delivery of the force. 

By simply changing the posi- 
tion of the nut from one end of 

the long tube to the other, the 
Fig. 406. , . . r , r ' 

direction of the force exerted may 

be reversed, i.e., it may be made to exert a pulling or a pushing force 

from its base of anchorage. 

The form of traction screw illustrated in Fig. 406 is the design of 
Dr. Angle, its especial feature of value being that the point of delivery of 
the force may be always on a pivot through the engagement of the right 
angled end of the traction screw with a tube soldered to the band trans- 
versely to the axial diameter of the tooth which is to be moved. 

Its principal use is as an auxiliary to the expansion arch in securing 
certain individual tooth movements which cannot be so directly and 
accurately accomplished with the arch alone. 

Detailed descriptions of its use are illustrated in the chapter on 
treatment. 

Mechanical Advantage.— The dynamical features presenting in 
the correction of malocclusion, require that only that appliance should 
be used which shall possess the greatest mechanical advantage in its 
application, and consequently, conserving all of the energy possible, 
both of force and resistance. 

In the conformation of appliances to the principle of the conser- 
vation of energy, we must recognize the primary axiom, "the work 
done by the effort must equal the work done in overcoming the resist- 
ance," and that the test of the efficiency of any appliance is the nearest 
approach to the securing of resistance and application of force which 



DYNAMICS AND ANCHORAGE. 57 1 

shall be the most useful and the least wasteful of the energy which is 
being used. 

"If a machine could be made which wasted no energy, the resist- 
ance being all useful, and not wasteful, the machine would be perfect, 
and its efficiency would be unity." 

Theoretically, we can imagine an appliance for moving teeth, having 
every mechanical advantage, sufficient resistance in anchor teeth, 
sufficient and controllable potential, and direct application of its force, 
with no loss of energy at any point, but in practice we are confronted 
with such obstacles as friction, insufficient and unstable resistance, in- 
direct application of force, etc. 

The efficiency of any appliance, therefore, can be expressed in a 
proper fraction, or a percentage of the total amount of energy put into 
it. 

Simplicity of construction and operation is a prime factor in the 
determination of the efficiency of an appliance, since the least number 
of working parts reduces the amount of friction and other wasteful 
energy. 

The stability or fixation of the basal attachments of an appliance, 
the material of which they are constructed, the size and temper of 
wires and ligatures, and the amount of power capable of being pro- 
duced, are likewise essential factors in the efficiency of any force pro- 
ducing mechanism used in orthodontia. 

It is obvious that an appliance should not only have the most sta- 
ble attachments, sufficient resistance to the applied force, which is 
most direct in its application, but also that the force itself should be 
great enough and under such control that the time, rate, or power of 
accomplishment of certain desired tooth movements may be somewhat 
accurately gauged. 

Resistance Values in Anchorage. — The first study of resistance 
values in anchorage should naturally be that of the teeth, individually 
and collectively in occlusion. 

The integrity of the arches of teeth in occlusion exhibits such 
equilibrium of force and resistance in its maintainment through the 
anatomical construction and the order and economy of arrangement, 
that perfection of contour and stability of structure are assured. 

The interdigitation of the cusps of the teeth, the length of the over- 
bite, the proximate contact, the forms and sizes of the teeth, all con- 
form to the requirements of function and structure so uniquely, that 
in the performance of their natural function of mastication, the ana- 
tomical structure is conserved or maintained in its integrity. 



57- 1 ORTHODONTIA. 

Likewise in the study of resistance values is to be considered 
the relative thickness of the alveolar process of the arches of teeth, 
and the lesser resistance to mesial than to distal movement of both 
upper and lower teeth; as well also, the age at which correction of 
malocclusion is begun, and the lesser density of the alveolar process 
in the earlier years of childhood affording the best opportunity for 
treatment, since the cartilaginous structure of the alveolar process, 
together with the lesser number of permanent teeth, if any, present, 
offers the minimum amount of resistance to tooth movement. 

Anchorage is the resistance selected as a base from which force is to 
be delivered for the movement of teeth. 

This resistance may be obtained from the teeth singly, or in multi- 
ple, or from the top and back of the head by means of the headgear, and 
except in reciprocation of anchorage, should always be greater than the 
force to be delivered from it in the movement of teeth. 

The laws of action and reaction govern the application of force 
appliances to the teeth, and a failure to observe their requirements in 
the securing of sufficient anchorage for any tooth movements, will 
certainly result in the failure of production of the desired results, as 
w r ell as dangerous tipping and displacement of the anchor teeth in some 
cases. 

Efficiency of Appliances. — The efficiency of any appliance de- 
pends upon, first, sufficient anchorage; second, the direct application 
of force in the direction of the desired movement; third, the skillful 
manipulation of the appliance so that the least resistance will always 
be offered to the applied force, thus conserving the f anchorage; e. g. 
in the restoration of inlocked laterals to occlusion, a proper conserv- 
ation of anchorage would require that the space for the laterals in the 
arch be first obtained before attempting their movement into line. 

The cast on the left of Figure 407 illustrates a case of this character 
before treatment. If the laterals were ligated to the arch together 
with the centrals and cuspids at the beginning of treatment, the resist- 
ance to forward movement of all of these teeth would be greater than 
that of the molars to distal movement, and the anchorage would soon 
be weakened to such an extent that the case could not be completed 
without resting the anchor teeth for some time. The cast on the 
right of this figure illustrates the manipulation of the expansion arch 
so as to offer the least resistance during the entire treatment of the case, 
the centrals being ligated first, the cuspids and the bicuspids next, and 
when sufficient space has been made for the laterals , they, too, are 
ligated and drawn into alignment. 



DYNAMICS AND ANCHORAGE. 573 

The stability of teeth used for the anchorage appliance varies with 
their power of resistance, which is determined by their size and loca- 
tion, the length and number of their roots, and the direction and manner 
of application of the required force, as well as the period of development 
of teeth and process. 

From the size and number of their roots and advantageous location 
in the posterior part of the arch, the molars are most commonly selected 
as anchor teeth. 

Comparative Measures of Resistance. — Anchorage is largely a 
question of comparative measures of resistance, each individual tooth 
having a certain resistance value, which varies with its normal or 




Fig. 407. 

malocclusion, and whether it has teeth adjacent to it or not. By first 
moving the teeth adjacent to the inlocked lateral in Fig. 407, the 
greatest resistance to their movement is removed. 

Simple anchorage is the obtaining of a sufficient resistance in one 
part of the arch for tooth movement in another part of the same arch, the 
anchorage resistance being relatively greater than that of the teeth to be 
moved, although admitting of some instability of the anchor teeth. 

Re-enforced anchorage is the adding of the resistance of teeth in 
the same arch or opposite arch, through the use of other forms of anchor- 
age, as auxiliaries, in combination with the already established simple 
anchorage. 

Reciprocal anchorage represents the counterbalancing of anchorage 
resistance between teeth located in different parts of the same arch, or in 
opposite arches, to the mutual advantage of tooth movements. 

A combination of several of the various forms of anchorage which 
may be secured in the same arch is exhibited in Fig. 408. 

Simple anchorage would be here represented by the first molars 



574 ORTHODONTIA. 

in their opposition to the movement of the three incisors, B, B, B, which 
are Ligated to the arch, the measure of the resistance of the latter teeth 
being comparatively less than that of the first molars to distal move- 
ment. 

If the forward movement of the cuspid were attempted without 
re-enforcement of the anchorage, as in the ligation of the second bi- 
cuspids to the molars at D, undue tipping of the first molars might fol- 
low with the loss of simple anchorage. 

In lateral expansion of the arch, without much forward movement 
of the incisors and cuspids, the simple primary anchorage of the first 
molars is usually sufficient, and also in many cases of forward move- 
ment of the six anterior teeth, if the second molars are present to add 
their resistance to the first molars to distal movement. 




Fig. 408. 

Reciprocal anchorage in connection with the expansion arch, is a 
secondary anchorage, and is represented in Fig. 408, A, A, B, B, B and C. 

The resistance of the right cuspid to buccal movement through 
its ligation to the arch is opposed and counterbalanced by a similar 
attachment of the left cuspid to the arch at A, and neither affecting to 
any degree, the primary first molar anchorage, since their lines of re- 
sistance are at right angles to the established line of resistance. 

The expansion arch being a reciprocating spring, attachments to 
the arch as at B in the rotation of a lateral can be made to perform 
tooth movement through this reciprocating tendency, especially when 
aided by the rubber wedge. 

The two centrals ligated together, are reciprocating in their re- 
sistance to mesial movement, and at the same time reciprocating force, 
from the ligation to the arch as B, B, is rotating them in their sockets. 



DYNAMICS AND ANCHORAGE. 



575 



The lever also, at C, exerts a reciprocal force in the rotation of the 
right lateral incisor. 

The banding and ligation of the second bicuspid to the first molar 
anchorage serves as a sufficient re-enforcement of this anchorage, for 
the tooth movements to be made. 

Without considering in this connection the advisability of the extrac- 
tion of the first bicuspid, and retraction of the cuspid into its space in a 
case of Class II, Div. n, Subdivision (Angle), it may be well to illus- 
trate, in Fig. 409, a form of anchorage devised by Dr. Angle, the applica- 
tion of the traction screw and expansion arch in efficient combination 
for the successful attainment of the result desired of harmonizing the 




Fig. 409. 



size of the arches without shifting the occlusion in the molar region, an 
operation which is unnecessary from the standpoint of perfect occlusal 
restoration, yet is here illustrated for the purpose of exhibiting the re- 
ciprocation of force from one appliance to the other in the attainment of 
the result. 

It will be observed that the long sheath of the traction screw is 
attached directly to the molar clamp band, and the short tube on the 
cuspid band, which engages the right angled end of the traction screw 
is attached at one corner only, at right angles to the direction of the 
desired movement. 

The expansion arch is supported by a short tube soldered to the 
under side of the forward end of the sheath of the traction screw on 
this side, the other end being supported by the usual tube on the molar 
clamp band. 

The reciprocating of the force acting to rotate the incisors through 
the forward movement of the expansion arch, to the distal movement 



576 ORTHODONTIA. 

of the traction screw in drawing the cuspid backward, is the feature 
of especial value. 

The Case Reciprocating Arches. — One of the most ingenious 
examples of a reciprocal and a re-inforced anchorage is embodied in 
the principle of an appliance in Fig. 410, devised by Dr. C. S. Case. 

It consists of two buccal arches, supported by tubes soldered to 
each other at slightly diverging angles, the inner one united to a molar 
band and supporting a threaded arch of about 19 gauge, which is 
attached to the incisal ends of vertical bands upon tbe incisor teeth, 
the outer tube supporting an ordinary expansion arch, which is some- 
what flattened as it engages with hooks at the gingival end of the same 
vertical bars upon the incisor bands. 




Fig. 410. 

Turning up the nuts in front of the tube supporting the upper arch, 
the roots of the incisors are pushed forward and the crowns inhibited 
in movement or retruded slightly as desired by control of the nuts 
behind the anchor tubes supporting the lower arch. The resulting 
effect of these opposite acting forces is to produce an equilibrium of 
forces in the region of the molar anchorage, and this unique application 
of the arches can be classed under reciprocal anchorage when the force 
and resistance are equally balanced. The necessity of the use of this 
appliance also, has greatly diminished since the utilization of other 
simpler forms of anchorage in the shifting of the occlusion of the teeth, 
mesially or distally, has come to be more generally understood. 

Stationary anchorage represents an anchorage which is stable and 
unvarying in its resistance for tooth movement. 

Although stationary anchorage in the absolute, is probably never 
secured in the mouth, yet in the use of the expansion arch for move- 
ments of one or two incisor teeth, in which the primary anchorage is 
re-enforced, there is no doubt that stationary anchorage is secured, at 
least to all practical purposes. 



DYNAMICS AND ANCHORAGE. 577 

First Molar Anchorage. — The first molar is so often chosen as 
an anchor tooth for the basal attachment of appliances in the correc- 
tion of malocclusion, because of certain anatomical and mechanical 
features that enter into the selection of an efficient anchor tooth. 

At six or seven years of age, the first permanent molar is usually in 
position, and, as its name implies, is the only permanent molar ready 
to be used as an anchor tooth. 

If the relations of these teeth are incorrect with their mates in the 
opposite arch, it is to them that attention has to be first directed and 
their relative positions corrected and retained until occlusion of enough 
of the permanent teeth has been established to secure the normal rela- 
tionship of the arches as a whole. 

Again, later in life, when the second molars have erupted, the use 




Fig. 



of the first permanent molar as an anchor tooth receives an efficient 
re-enforcement to its resistance to tooth movement anteriorly, from the 
fact of its being supported by the second molar and the strong alveolar 
process surrounding it. 

The roots of the first molar are also more diverging than those of 
the second, so that the first molar has a greater comparative resistance 
value than the second molar because of the greater force required to dis- 
place it. 

The eruption of the third molar adds still greater resisting power 
in movement of teeth anteriorly to the first molar as an anchor tooth. 

In the use of "fixed" appliances for the correction of malocclusion, 
an expansion arch, supported by clamp bands, upon molar or bicuspid 
teeth forms the usual basal attachment in each arch of teeth for the ob- 
taining of sufficient resistance for the tooth movements in that arch. 

Primary Anchorage. — This attachment to single molar or bicuspid 

37 



5;S ORTHODONTIA. 

tooth, on each side of the arch, may be designated as primary anchor- 
age (Fig. 411). 

Secondary Anchorage. — Should it be desired to add the resistance 
of other teeth in the same arch, or in the opposite arch, or the resist- 
ance from the teeth of the opposite arch, the additional anchorage 
obtained would be designated as secondary anchorage, and would in- 
clude any of the other forms of anchorage. 

It will be seen that in the use of the expansion arch, the control of 
all the units of resistance of individual teeth within the arch is obtained, 
and usually by the simple attachment of ligatures around the teeth 
and over the arch. 

Often the arch is ligated to the incisors firmly, simply as a secondary 
anchorage, or support for the arch, during the movement of cuspids or 
bicuspids to alignment. 

It is necessary in many cases, to secure the resistance of the arch 
as a whole, to oppose tooth movement in the opposite arch, when the 
resistance of every tooth in the arch may be obtained by proper 
ligation. 

Mention has already been made of the use of ligatures in connection 
with the expansion arch for the purpose of securing the added resist- 
ance of individual teeth to the primary established anchorage, and the 
attachment of ligatures for adding resistance, or for tooth movement, 
varies but little, if any. 

In order to secure the direct application of force in the direction of 
the desired movement, a knowledge of the relative position of a tooth 
to the "line of occlusion," will, by indication of its malposition, whether 
in labial, lingual, mesial, distal, infra-, supra-, or torso- malocclusion, 
enable one to determine the exact direction in which the force should 
be applied. 

This being determined, the application of the force from the expan- 
sion arch is obtained by the firmest attachment of the ligature to the 
tooth that is essential. 

If there should be any possibility of slipping, or if rotation is neces- 
sary, the use of the Magill band with lugs, is a necessity, as a continued 
slipping off of ligatures will delay the completion of a case for months. 

Intermaxillary anchorage is the opposing of the resistance of the 
teeth in one arch against that of the other, partially or completely, to the 
advantage of tooth movement in the arch in which the lesser resistance 
is established. 

This is secured by the attachment of rubber elastics from one arch 
to the other, exerting a force termed intermaxillary force. 



DYNAMICS AND ANCHORAGE. 



579 



Fig. 412 illustrates the application of the intermaxillary elastics to the 
Angle expansion arches and clamp bands, for shifting the occlusion in 
Classes II and III, being attached in Class II from hooks upon the 
upper expansion arch to the distal end of tube on lower molar clamp 
band, and in Class III from hooks upon the lower expansion arch to 
the distal end of tubes on upper molar clamp bands. 

The use of intermaxillary anchorage is called for in all classes of 
malocclusion, either for the direct application of intermaxillary force 
or for purposes of auxiliary resistance, and will be further described 
under treatment. 

Uses of Intermaxillary Anchorage. — Briefly stated, the various 
methods of application of intermaxillary anchorage are as follows : 





Fig. 412. 



The use of either arch of teeth, en phalanx, as anchorage for the 
attachment of the rubber ligature to effect the movement of one or 
more teeth in the opposite arch. 

The upper arch used (en phalanx) as resistance for the consecutive 
mesial movement of the lower incisors, cuspids, bicuspids, and molars. 

The lower arch used (en phalanx) as resistance for the consecutive 
mesial movement of the upper incisors, cuspids, bicuspids and molars. 

The use of either arch of teeth in whole or part as anchorage for a 
simultaneous mesial movement of teeth in one arch and a distal move- 
ment of teeth in the other. 

The use of the intermaxillary anchorage to sustain, or as an auxiliary 
to other established methods of anchorage. 

The elevation of teeth in either arch. 

The use of intermaxillary anchorage between single teeth of oppo- 



580 ORTHODONTIA. 

site arches, in opposing their resistance to mutual advantage in mesial 
or distal, and buccal or lingual movement. 

The reciprocation of the movement of teeth in the use of inter- 
maxillary anchorage, is not claimed, although it may and does occur 
under proper conditions, as when the anchorage resistance in one arch 
exactly balances that of the other. 

It is necessary to distinguish between intermaxillary anchorage and 
intermaxillary force, the former referring to the opposing of resistance 
of teeth of maxilla and mandible, the latter to the force, which in the 
use of the rubber elastic, must be equally exerted on teeth of both 
arches. 

Intermaxillary force is always reciprocal ; intermaxillary anchorage 

may be reciprocal or not, i. e., the 
resistance in one arch may be equal 
to that of the other, or it may be 
greater or less. 

Intermaxillary anchorage is a 
valuable adjunct in Class I, in 
which it is not desirable to change 
the molar occlusion. An example 
of its use in a case of this class is 
seen in Fig. 413, the expansion arch 
on the upper arch of teeth being 
adjusted so as to regain the space 
for a second bicuspid, the resistance to a forward movement of the 
anterior teeth falling entirely on the first permanent molar, which is 
prevented from distal movement by an intermaxillary force acting in 
the opposite direction through the attachment of the intermaxillary 
elastic to a hook in the region of the cuspid on lower expansion arch. 
It will be observed that the resultant of these two opposite forces 
can be made to be zero — by a proper gauging of the strength of the 
elastic — thus preserving the stability of the first molar, as is desired. 
Occipital anchorage is the resistance obtained through the use of the 
top and back of the head in connection with the headgear for assisting 
tooth movement or maxillary and mandibular movements not obtained by 
other forms of anchorage. 

This valuable form of anchorage has dropped somewhat into disuse, 
because of the splendid results which are now obtainable by the use of 
the intermaxillary anchorage. 

The chief use of this method of anchorage was formerly in connec- 
tion with the treatment of Class II and III cases, in which the anchor- 




Fig. 413- 



DYNAMICS AND ANCHORAGE. 



581 



age within the mouth was not sufficient to meet the requirements of 
the case. 

Fig. 414 shows the Angle headgear and traction bar in position for 
the application of occipital anchorage, the socket of the traction bar 
engaging with the ball soldered on the front of the expansion arch. 

Occipital anchorage is seldom indicated except in unusually re- 
fractory cases of Class II or III, in which it is an efficient auxiliary. 

Summary of Anchorage Principles. — In summing up our re- 
marks on the subject of anchorage, we are led to the following con- 
clusions : 




Fig. 414. 



First, that the primary principles of force and resistance in action 
and reaction apply equally well in the attachment of the applicances for 
orthodontia as in other machines. 

Second, the subject of anchorage resolves itself into that of compara- 
tive measures of resistance, always, however, with the securing of a 
greater resistance at the base of attachment of an appliance than that 
to be overcome at the point of delivery of the force. 

Third, that the applied force shall be sufficient for the required 
tooth movements, and under perfect control. 

Fourth, that the force be applied in the most direct manner for tooth 
movement, but not so rapidly as to endanger its own basal attachments, 



582 ORTHODONTIA. 

or cause undue strain on the teeth and consequent pain, or loss of the 
anchorage. 

Fifth, that the force producing appliance be simple and yet correct 
in principle for the restoration of normal occlusion. 

Sixth, that the addition of re-enforced anchorage of any kind is 
advisable where the primary anchorage is not sufficient for the desired 
tooth movements. 

Seventh, that advantage should be taken of reciprocal anchorage 
whenever possible, either in the same arch, or opposing arches, for 
sustaining the stability and integrity of the primary anchorage, as well 
as increasing the efficiency of the appliance. 

Eighth, in the use of intermaxillary anchorage, especially in con- 
nection with the primary established anchorage in both arches, the 
greatest attainment in the scientific application of anchorage is achieved, 
and the most difficult results obtained in the treatment of malocclusion. 

Ninth, that the appliances must be kept up to their highest standard 
of efficiency at all times during the progress of treatment in order to 
conserve anchorage and the length of time for operation. 

VI. OPERATIVE TECHNIQUE. 

Qualifications of Appliances. — The chief qualification that an 
appliance should possess is that of efficiency, the virtue of simplicity 
of construction naturally being included, since it is the sine qua non 
of all machines which have proven of any value in the scientific world. 

The efficiency of an appliance for the correction of malocclusion 
consists of the fewness and proper proportion of adaptable parts, ca- 
pable of appropriating sufficient and varied forms of anchorage, and 
having within its compass the positive control of all of the teeth of one 
dental arch, conserving time and energy through the proper adjust- 
ment of each part so as to secure a perfect working mechanism, ca- 
pable of transmitting force as rapidly and in such quantity as is con- 
sistent with physiological maintenance in operations on vital structures. 

Simplicity in appliance construction and efficiency in operation 
has evolved the modern expansion arch, which, examined very care- 
fully with its anchor bands, Fig. 415, will be found to possess certain 
characteristics which stamp it as the most superior of all appliances 
for the complex requirements in orthodontia. Chief among these 
qualities are its universality of application and efficiency of mechanism. 

Its principal mechanical features are its possession of the principles 
of the spring and the screw, the center of the spring being in the 
center of the bow of the arch, which, from end to end, presents the 



OPERATIVE TECHNIQUE. 583 

appearance of a double jack-screw, with all the advantages of the fine 
gradations, yet strong and efficient force of the screw principle. 

When anchored in position upon molar clamp bands upon the 
teeth, it can be used as a reciprocating spring for the balancing of force 
and resistance from one side of the arch to the other, for lateral and 
anterior expansion, and for the rotation and elevation of teeth within 
its compass, and as a base of anchorage for tooth movement in the 
opposite arch. 

Whether constructed of gold or German silver, the expansion arch 
should be possessed of a very hard temper, so as to be capable of 
the greatest possible amount of spring for expansion purposes, and 
should be furnished in sizes according to the size of the dental arches, 
and degrees of resistance to be encountered. 




Fig. 415. 

The author prefers three different gauges, 16, 17, and 18 Brown 
and Sharpe gauge, the smaller sizes being especially adapted for 
treatment of malocclusion in the small mouths in which the deciduous 
teeth are predominant in number, and the larger size for the adult 
arch, in which greater strength is required. 

Adaptation of the Arch. — While possessing a very hard temper, 
the expansion arch is capable of being bent to any form which is most 
adaptable to the case in hand, care being taken to make the bends 
with the round nosed portion of the arch and ligature pliers (Fig. 431) 
so as to avoid breaking the wire. 

The general form the arch should assume for any case should be 
determined somewhat by the normal arch as pre-determined by the 
method illustrated in the chapter on diagnosis. However, in many 
cases, the arch in this form would be so large that it would extend too 
far outward from the labial and buccal surfaces of the teeth for 



584 ORTHODONTIA. 

comfort, and the ligatures would have a tendency to slip off from the 
teeth because of their unusual length, so that the anterior arc will 
have to be made a little shorter at first and later on changed as it 
is found that the increased expansion of the arch will allow of enlarging 
the arc to the size of the pre-determined arch. 

Often it will be necessary to bend the arch wire in and around 
a certain tooth which is so far in labial or buccal occlusion that it 
interferes with the adaptation of the expansion arch to the rest of the 
teeth to too great an extent for comfort or practicability. 

These bends may be gradually worked out as the case progresses, 
and the arch is restored to normal size and shape: 

The tendency of the amateur is to give the expansion arch too 
much lateral spring when first applied, and to force the incisors and 
cuspids forward by turning up the nuts in front of the anchor tubes, 




Fig. 416. 

too frequently, instead of performing sufficient lateral expansion, 
both anteriorly and posteriorly. 

It is advisable in any case, to adjust the expansion arch to its posi- 
tion for a few days without any lateral spring in it, so as to allow the 
patient to become used to the bulk alone at first, and afterward, 
increase the lateral spring to suit the case. 

In the expansion of the anterior portion of the arch only, it is 
necessary to have but little lateral spring in the expansion arch, and 
it should conform to the labial surfaces of the incisors and cuspids, 
as w T ould be secured in the short arc BB, Fig. 416, for cases of slight 
expansion or the movement of one or two incisors into normal positions, 
but in severe cases, and in those in which considerable lateral develop- 
ment is desired, the bow of the expansion arch should be bent with the 
arch and ligature pliers so as to form a longer arc, CC, the ends of the 
arch slipping into the anchor tubes with the lateral tension gauged 
according to the amount of posterior expansion indicated by diagram- 
matic measurements. 

Whenever it is necessary to provide for considerable anterior 




OPERATIVE TECHNIQUE. 585 

expansion, such as in a case in which the cuspids are in labial occlusion, 
it will always be found necessary to expand posteriorly as well, and in 
fact the Hawley diagrams of the pre-determined arch indicate anterior 
and posterior expansion in the majority of cases, and the arch should be 
bent so that it will have sufficient lateral spring to meet the require- 
ments of the case, remembering that the difference in resisting power of 
the teeth and alveolar process is varied according to the age and number 
of permanent teeth present. The adult arch will resist an expansive 
force which would be impossible to use in the case of an arch in which 
the deciduous teeth were not all shed. 

The author has found it advantageous and conservative of anchor- 
age to perform anterior expansion in advance of very much posterior 
expansion in many cases, since the re- 
sistance power of the molar anchorage 
is only opposed in one direction 
through the turning up of the nuts 
in front of the anchor tubes, while 
in performing anterior and posterior 
expansion simultaneously, the resist- 
ance power of the molar anchorage FlG . I7 
is being opposed in a lateral as well 
as a distal direction, tending to make it more unstable than by the 
other method. 

Bodily Control of Anchor Teeth. — The round buccal tube on 
molar clamp bands which receives the round end of the expansion arch 
allows of a bucco-lingual tipping of the anchor teeth which is not 
especially desirable in many cases. 

One of the best methods of obviating this difficulty is the use of 
the square hole buccal tube, and square ended expansion arch illus- 
trated in Fig. 417, as designed by Dr. F. C. Kemple. 

Their adjustment is a matter of some little care as to the detail 
in order to secure an accurately fitting and efficient appliance. 

The square hole tubes are first soldered upon the buccal surface 
of the molar clamp bands, according to the alignment of the plain 
expansion arch which is slid into the square orifices for this purpose. 
The surplus length of the expansion arch extending beyond the distal 
end of the tubes is then cut off, and its ends filed square to fit a smaller 
square holed tube which perfectly fits the larger buccal tube on the 
clamp band. These smaller tubes are about one-eighth of an inch 
long, and should be soldered upon the filed ends of the expansion arch 
one at a time, being careful to preserve the proper relations with the 



586 ORTHODONTIA. 

larger buccal tubes by such adjustment of each of the smaller tubes 
upon the ends of the expansion arch as will preserve its proper align- 
ment and allow it to slide easily to position. 

The arch may be manipulated by turning up the nuts in front of the 
anchor tubes, or as any expansion arch adjusted with the round tubes 
on the molar clamp bands. 

Any lateral spring in the expansion arch will be exerted upon the 
anchor teeth in such a manner as to move them bodily through the 
process. 

The application of the square hole tube upon one side of the 
dental arch, and the round hole tube upon the- other, is often of ad- 
vantage in securing stationary anchorage upon the lateral half upon 
which the square hole tube and square end of the expansion arch is 
used. 




Fig. 418. 

The Divided Expansion Arch. — In order to obviate the removal 
of the plain expansion arch at intervals to rebend the anterior portion 
into a larger arc to meet the requirements of increased expansion 
the author has been using the divided expansion arch illustrated in 
Fig. 418, especially in extreme cases of expansion, to a decided advant- 
age over the plain arch. 

The principle is not entirely new, except in its application to the 
outside of the dental arch, for the purpose of anterior expansion, 
The author is indebted to Dr. L. P. Bethel for valuable suggestions 
and assistance in the application of the divided arch principle. 

This arch has the power of four jack screws and at the same time 
retains the elasticity and power of the reciprocal spring as exhibited in 
the plain arch if it is properly made. It also can be made to exert force 
in the directions indicated by the arrows in the illustration, Fig. 419. 

The divided ends of the arch fit snugly into the central tube, so 



OPERATIVE TECHNIQUE. 



587 



that the lateral spring of the two halves is as great as in the undivided 
arch. It is adjusted the same as the plain arch, and can be used in 
Class II or III, where considerable expansion and a mesial or distal 
change in the occlusion is needed at the same time. 




Fig. 419. 

With this divided arch the operation of expansion is performed 
in one-third of the time that the same work is done with the plain ex- 
pansion arch. 

Another form in which the divided arch may be constructed is 
shown in Fig. 420, a long central nut, being right and left threaded from 




Fig. 420. 



each end to the center, operates upon each lateral half of the arch, 
which are threaded to correspond. This arch has the power of six 
jack screws, having the power of contracting by reversing the direction 
of the nut from that which is necessary in expansion. 

Being composed of fewer pieces, this arch is a little simpler, al- 




$88 ORTHODONTIA. 

though not being so perfectly adaptable to a rounded arch on account 
of the long straight nut in the center. 

Adjustment of Anchor Clamp Bands.— In the adjustment of 
the anchor clamp bands to molar or bicuspid teeth, the lingual nut 
should first be loosened, and the circumference of the band made to 
correspond somewhat to that of the tooth it is to placed upon, bending 
the lower edge to the tooth form, after which it is slipped over the 
crown of the tooth with the fingers, the lingual screw 
pointing mesially, and gently but uniformly pressed be- 
tween the adjoining teeth on each side. Usually, the 
bands can be forced into place with the thumbs, pressing 

F it downward uniformly mesially and distally, but occa- 

sionally it will be necessary to apply a stronger pressure 
on each mesial and distal upper edge of the band with a flat bone 
spatula and with the band driver working it downward alternately, 
lingually and buccally, over the swell of the crown. 

When in position, the anchor clamp band should have the appear- 
ance of the band fitted to a molar tooth in Fig. 421, the lingual nut being 
screwed tightly down, with the end of the threaded wire close to the lingual 
surfaces and the upper edge of the band burnished into the buccal 
groove and against the inclines of the cusps. A very efficient form 
of burnisher, in right and left patterns, and heavy octagonal handles 
affording a very secure grip, and designed by Dr. Murless, is illustrated 
in Fig. 422. Anchor clamp bands should be cemented into place at 
the first sitting after its adjustment with expansion arch in correct 
position, so that it will easily slip into position, and not have to be re- 
moved for alignment of anchor tubes, etc. 

If the bands are to be left on but two or three months, they may 
be set with chloro-percha or gutta-percha, which fills up the intervening 
space between band and tooth, and prevents any tendency to caries. 

Wrenches. — As the wrench is the most commonly used instrument 
of the orthodontist, it should be so constructed that it will represent 
in material of construction, adaptation and finish, the most perfect 
of instruments. In the first place, it should be made of steel, which 
allows greater rigidity with less bulk than iron. The handle should be 
octagonal, giving a firm grip, and the whole instrument about 5-5- inches 
long. 

The socket ought not to be deeper than the width of the nut, and 
should fit quite accurately. The arms of the socket should be circular 
in form tapering down upon the handle. 

Fig. 423 represents the double ended oblique angled instrument. 



OPERATIVE TECHNIQUE. 



589 



Band Driver. — The band driver should primarily have a large 
handle which will afford a strong grip, and the tip should have a groove 
which will engage with the top edge of a band. Fig. 424 is a band 





driver of this character, which may also be used for bending the ends 
of ligatures out of the way under the arch. 

Bucco-lingual Alignment of the Anchor Tubes. — If the clamp 
band is one in which the buccal tube is soldered directly to the band, 



^QO 



ORTHODONTIA. 



care should be taken in adjusting the band so that the tubes will be 
aligned parallel to the buccal cusps of the molar, or if a bicuspid, 
parallel to the buccal surfaces of the bicuspids, so that the expansion 
arch may be easily slipped into the tubes without unequal tension at 
either mesial or distal end of the tube on either anchor clamp band. 
Fig. 425 illustrates diagrammatically the relationship of the expan- 
sion arch to the tubes on anchor clamp bands, B and F, representing 
the positions of anchor tubes in which the ends of the expansion arch 
will slip easily and uniformly into them, and A and C, positions in 
which the tubes are so far from the parallel that the arch cannot be 




3P 



A BO 



Fig. 425. 



readily inserted, and which would be creative of unequal tension 
upon the molar to such a degree that rotation of this tooth would 
be inevitable, and the easy manipulation of the arch interfered with. 

Where it is desired to rotate the molar on which the anchor clamp 
band is placed, the end of the expansion arch may be bent lingually 
from a point in front of the nut as in D, Fig. 425, and the expansion 
arch sprung into place, causing the mesial angle of the molar to turn 
buccally and the distal angle lingually as suggested by Dr. E. H. Angle. 
A buccal bend as at E will cause the tooth to rotate in the opposite 
direction. 

Vertical Alignment of Expansion Arch. — Although the anchor 
tubes may be aligned so that they allow the arch to be readily slipped 
into them as just described, it will usually be found that the bow of 



OPERATIVE TECHNIQUE. 



591 



the arch is either too high or too low on the labial surface of the incis- 
ors, often as at AED, Fig. 426, the arch resting against the incisal edges. 
To establish a correct vertical alignment of the front of the arch without 
unsoldering the anchor tubes, if the upward or downward inclination of 
the arch is not too great, the mesial and distal edges of the band may be 
slightly raised or lowered so that the arch will rest against the labial 
surface of the incisors near the necks, and by burnishing the edges 



*-\ 



if i 



^ 



Bt===: 




Fig. 426. 



of the band tightly in these positions, and re-tightening the lingual 
nut, the security of the clamp band will not be, endangered. 

Another method that is of advantage in some cases is to bend the 
expansion arch in front of the nuts, as at E, Fig. 426, so the front of the 
arch will rest in its proper position, AEF, upon the labial surfaces of 
the incisors. 

The author prefers to unsolder the anchor tubes in case of any 
great variation from the desired alignment, and realign them so that 
the arch and anchor tubes will be in the same plane when in proper 




LA 



XJ 



> N 



Fig. 427. 



position, as at HN in Fig. 427, the force being delivered more directly, 
and the ligation of bicuspids to the arch being much more readily 
performed. The change of alignment by this method is very easily 
accomplished by the use of the soldering clamps as illustrated in Fig. 599 
in the chapter on constructive technique. 

The author prefers the anchor clamp band with the pivotal tube 
for many cases, as it allows of a change of inclination of the tube at any 
time before or during treatment, without unsoldering the tube or taking 
off the arch or clamp bands, the tube being attached by a short, round 



592 ORTHODONTIA. 

piece of wire to the clamp band, and capable of being twisted with 
the pliers upward or downward to any position desired, as in Fig. 90. 

The saving of time and the possibility of always keeping up the 
standard of efficiency in the arch through its being properly related to 
tooth surfaces is of great advantage in the use of this anchor clamp 
band. 

Ligatures. — After the proper adjustment of the arch and molar 
bands upon the teeth, a study of the case should be made with regard 
to the most advantageous use of the wire ligatures, so that the most 
direct and positive force may be exerted upon the teeth which are to be 
moved, and a proper balancing of the lateral expansive force obtained so 
that reciprocation of force may be secured from one side of the arch 
to the other. 



Fig. 428. 

At the present time, five sizes of ligature wire are in use for this 
purpose, their respective diameters being .013, .014, .015, .017 and 
.018 of an inch. 

For gentle traction force, the finest ligatures are most serviceable, 
especially in the movement of the deciduous teeth, and in the ligation 
of permanent teeth at the beginning of treatment when the proximation 
of the surfaces of the adjoining teeth render it difficult and some- 
times impossible to use the heavier ligatures. 

The heavier ligatures are suitable for accurate and efficient work 
in any position where they can be used, their efficiency increasing with 
their diameter. 

The greatest usefulness of the ligature is obtained only when the 
expansion arch is slightly free from contact with the teeth to be ligated, 
so as to secure the fullest spring of the arch wire outward where 
general expansion is desired. 

Spurs. — Again, the effectiveness of the ligature may depend upon 



OPERATIVE TECHNIQUE. 



593 



the fixedness and location of its attachment to the expansion arch, 
which may be accomplished by the raised spur upon the surface of the 
arch wire located in such a position as to cause the movement of the 
teeth in a certain desired direction. 

In one style of the Angle expansion arch, the same purpose is 
accomplished by filing a notch in a re-enforced ridge which is on the 
buccal surface of the arch wire, this notch interfering in no way with 
the tensile strength of the wire since it does not penetrate its surface 
(see Fig. 428). 




Fig. 429. 



Spur Pliers. — Spurs may be easily and quickly made on the plain 
arch by means of the arch wire barber, or spur pliers shown in Fig. 
429, an invention of Dr. L. S. Lourie. 

This instrument, applied while the arch is in position, seizes the 
arch firmly between its two beaks, and by a slight pressure upon the 
lever at the side, at the same time, a small chisel is forced against 
the surface of the wire at an acute angle, raising a spur, which is 
hardly perceptible to the eye, but which is capable of holding the 
heaviest ligature from slipping. 

When any particular barb or spur is no longer in use, it may be 
burnished down upon the surface of the arch wire, so as not to inter- 
fere with the lip or cheek. The spring of the arch is not in the least 
impaired by the spurs made in this manner. 
38 



594 



ORTHODONTIA. 



When a longer and stronger spur is required, it may be made of a 
half cylindrical piece of band material previously fitted to the arch 
wire, and having soldered to its convex surface a piece of 21 gauge 
German silver wire, as illustrated in Fig. 596. The concavity of the 
band material should be polished with a sandpaper disk, touched with 
a drop of phosphoric acid, and a small portion of soft solder melted 
into it, after which it is united to the arch in the desired position and 
the end cut off to the length required, and finished with the disk so as 
to leave no rough surface to the cheek. 




Fig. 430- 



Variety of Ligatures. — The advantages to be gained by the use 
of a variety of styles of ligatures may be understood from a com- 
parative study of the different methods of attachment to the arch 
according to the desirability of the attainment of such qualities 
as directness and positiveness of action, freedom from pain, and 
inconspicuousness of appliances through the use of the least number 
of bands upon incisors. 

The most commonly used ligature is that illustrated at A upon 
the first bicuspid in Fig. 430, and is properly used in ligating teeth 



OPERATIVE TECHNIQUE. 595 

which are to be moved in a straight line outward to the arch, without 
rotation. 

When the direction of the tooth movement is forward and outward, 
especially if rotation is necessary at the same time, as in the case of the 
lateral incisor at B, Fig. 430, the band with lingual spur should be ce- 
mented upon the tooth, and the direction of the ligature guided by the 
location of a spur on the arch wire. As soon as the teeth which need 
rotation approach the arch sufficiently near, the rubber wedge should 
be placed between the arch and the nearest approaching labial angle 
of the tooth, as in the manner of rotating the central incisor at H in 
the same figure. 

In favorable cases, the band need not be used, but the double loop 
ligature, shown at C, suggested by Dr. Angle, will be found serviceable 
in rotation. 




Fig. 431. 

In the ligation of bicuspids to the arch, the plain ligature often has a 
tendency to slip under the gum at the neck of the tooth, and not only 
cause pain but possible injury to the peridental membrane. To 
prevent this, the stirrup ligature, suggested by Dr. Lourie, and shown 
in position on the bicuspid at D, Fig. 430, is most efficient, the loop ex- 
tending across the sulcus of the bicuspid and soft soldered to the plain 
ligature at the mesial and distal angles of the lingual surface of the tooth 
effectually preventing any movement of the ligature toward the gingiva. 

A modified form of this ligature, known as the T ligature, has 
been devised by the author for the prevention of the slipping of liga- 
tures upon the deciduous teeth, the necks of which are so constricted 
that plain ligatures invariably tend to slip beneath the gingiva, a class 
of cases in which the greatest care should be taken that there is no 
discomfort from this cause. The T ligature is seen at F and E, Fig. 430, 
and is constructed by soft soldering one piece of ligature wire at right 
angles to another, the one ligature at right angles being carried over 



500 ORTHODONTIA. 

the occlusal surface of the tooth to engage in the twist of the other 
two ligature ends which pass through the interproximate spaces to the 
arch wire, one above and the other below. 

By forming a curved hook upon the end of the ligatures before 
inserting, they will easily pass through the interproximate space 
without injury to the gum tissue, as the ligature will follow this curve 
upward or downward through the space until it reappears free from 
the gums' on the lingual or buccal surface of the teeth. 

Ligatures should be pulled taut over the buccal surface of the 
arch, and pressure between the tooth and arch brought to bear with 
the thumb and finger, the long end of the ligature then being grasped 
with the left hand, and the short end with the arch and ligature pliers 
illustrated in Fig. 431, and twisted a full turn to the left, preferably 




Fig. 432. 

always twisting in the same direction. The ends of the ligatures should 
be clipped to one-eighth inch lengths and bent either above or below 
the arch to positions where they will cause no irritation. 

The arch and ligature pliers, devised by the author, have rounded 
beaks except the tips, so that the lips or cheek will not be caught 
between them as in a flat nosed plier. They are useful also for bending 
the expansion arch to shape as previously described. 

An improved form of ligature cutting snips in which the points of 
the beaks are especially long and slender and which allow of a little 
more delicate work is illustrated in Fig. 432. 

Lingual Bar and Ligature. — The alignment of the lower incisors 
is sometimes easily effected by the use of a lingual bar to which is 
soldered one ligature to prevent displacement, and another ligature 
extending around the bar and through the interproximate space be- 
tween the central and lateral on one side to the arch wire. For 
example, in A, Fig. 433, one ligature on each side between the central 



OPERATIVE TECHNIQUE. 597 

and lateral, and encircling the lingual bar, will easily align the incisors 
without the use of a single band, even where there is considerable 
torsion of any of these teeth. 

Closing up Spaces between Incisors. — If it is desired to close up 
spaces between the incisors, the ligatures may be applied in the manner 
shown in Fig. 433 at B, the two centrals being surrounded by a single lig- 
ature which also encloses the arch; at the same time, the laterals on 
either side may be similarly ligated to the centrals. This method 
obligation may be extended around as far as the second bicuspid to 
advantage in some cases. 





A B 

Fig. 433- 

Elevation of Cuspid. — In the elevation of the cuspid, the Magill 
band should be formed high up on the labial surface of the tooth, and 
soldered on this surface, and trimmed so that a projecting portion of 
the united ends of the band material is left for the attachment of a 
ligature to the arch as in Fig. 434. This method of attachment of the 
ligature is to be preferred to the spur, and saves the time of soldering 
the latter to the band. 

The author has succeeded in having these ligatures made in a 
filled gold wire which possesses the softness of the annealed brass 
wire without the oxidizing of the latter, if used 
with the gold arch. The all gold ligature wire l\n\ /^\ 

may also be used if preferred. *^T r yi V "" 

The operator should form the habit of twist- ( ^ J 

ing all ligatures in the same direction, preferably fig. 434. 

to the left. The ligature wire may be econom- 
ically used by grasping the long strand with the left hand and the 
short one, about two inches in length, with the pliers in the right 
hand, and the twist should be a complete one, so as to avoid all 
danger of its being unloosened between sittings. 

In cutting off the surplus ends of the ligature wire, about one- 
eighth of an inch of wire should be left, which should be bent above 
or below and around the arch where it will not irritate the lips or 
cheek. 

The silk ligature is again coming into use, for in the hands of the 
skilled operator, it may be manipulated in such a way as to avoid the 



598 ORTHODONTIA. 

use of bands to a large extent, and rendering the operation less painful, 
and the appearance of the mouth more esthetic than when many bands 
and metal ligatures are used. 

Mesial and Distal Movements of Incisors. — The mesial or 
distal movement of incisors is often necessary, and can be readily 
accomplished by the use of the ligatures alone in connection with 
spurs upon the arch for directing the movement as desired, as in 
Fig. 435. The spurs are made upon the arch so as to incline the 
ligatures in the desired direction, mesially or distally, and the nut 
at L is tightened, and at M is loosened, causing the arch to shift 
laterally in the direction of the arrow, JK, and carrying the incisors 
with it. The cuspids and bicuspids may be similarly ligated to the 
arch and share in the movement. 




Fig. 435- 

Distal Movement of Molars. — Oftentimes it is necessary, in 
opening up spaces for lost first molars, to pit the resistance of the ten 
anterior teeth against that of the second molars, which, in these cases, 
usually drift forward into the space of the lost first molars, and must 
be moved distally by a proper manipulation of the anchorage. 

Reversal of Base of Anchor age. —The reversal of the base of 
anchorage from the molars to the anterior teeth for the distal move- 
ment of the molars, may be effected by ligating a sufficient number 
of the anterior teeth to the arch so that their combined resistance will 
be greater than that of the molars to be moved distally. 

The combined resistance of the ten anterior teeth, as secured through 
ligation to the expansion arch as in Fig. 436, is greater than that of 
the second molars to distal movement, and turning up the nuts in front 
of the anchor tubes will force the molars distally and regain the spaces 



OPERATIVE TECHNIQUE. 



599 



of the lost first molars. The use of intermaxillary force as a re-en- 
forcement is advisable in many cases. 

To prevent the ligatures from slipping upon the expansion arch 
in the region of the bicuspids, spurs should be soldered upon the arch 
and the ligatures attached in front of them as at A and B, for securing 
the resistance of the second bicuspids more perfectly. The proxi- 
mate contact with the first bicuspids will suffice to obtain the re- 
sistance of these teeth in line with the required movements without 
spurs to attach ligatures. 

The arrows indicate the direction of tooth movement, in the region 
of least resistance, or the distal movement of the second molar teeth. 




Fig. 43 6 - 



Hooks may be attached to the expansion arch for the use of inter- 
maxillary anchorage, extending the elastic rubbers from hooks on the 
lower expansion arch to the distal ends of the anchor tubes of the 
upper expansion arch, in case the resistance of the single molars 
should prove to be greater than the anterior teeth to forward move- 
ment, thus preventing or inhibiting such undesired movement. 

As there may often be found in these cases some distal positions 
of the anterior teeth as a whole, having traveled distally into the 
space of the lost molars, it may be found necessary to use the second 
molars as simple anchorage at first, and successively move the anterior 
teeth forward, ligating and moving the two centrals, then the two 
laterals, and the cuspids next, and so on, turning up the nuts, in 
front of the anchor tubes and reversing the anchorage to the anterior 
teeth for the distal movement of the molars as soon as the anterior 
movement of the incisors and cuspids is well started. 

A traction screw operating on the lingual side of the molar clamp 
band directly against the bicuspid, as at C, will materially assist in 



600 ORTHODONTIA. 

opening up the space for the lost molar because of the positive char- 
acter of the force applied in as direct a manner as possible. 

Spaces occurring between the anterior teeth during their forward 
movement, should be closed up by ligating the anterior teeth in pairs 
from either side of the median line, as in Fig. 433-B, the centrals 
being ligated together first, and the laterals to the centrals, etc. 

Another method of closing up these spaces is by placing barbs on 
the surface of the expansion arch in such mesial positions that they 
will, through the ligatures, direct the teeth toward the center in their 
forward movement. 

If the resistance of the second molars in the movement of the 
anterior teeth, forward, should prove to be insufficient, as indicated by 
their becoming unstable, or moving too rapidly or too far, the inter- 
maxillary elastics may be attached from the distal ends of the lower 
molar anchor tubes to hooks placed upon the sides of the upper 
Q expansion arch, and thus inhibit 

^^^^jjjjjjgpnzjizzijr^^------^^^ further instability and allow of the 

continuation of the anterior move- 
FlG - 437- ment of the lower incisors, cuspids, 

etc., through this re-enforcement, until such time as the distal move- 
ment of the molars may require a reversal of the anchorage. 

Tipping Up Molars. — In cases like that just described, the second 
molar in its assumption of the first molar space, often tips forward to a 
considerable extent, requiring an adjustment of the anchorage, espe- 
cially to effect their restoration to upright positions during their distal 
movement. 

The tubes upon the anchor bands should first be so aligned that 
the ends of the expansion arch may be easily inserted into them, the 
bow of the arch resting upon the necks of the incisor teeth, as in 
alignment of arch and anchor tubes for ordinary expansion. 

The ends of the expansion arch should then be uniformly bent 
downward, beginning at a point just anterior to the nuts, as at G in Fig. 
437, and the arch re-inserted into the anchor tubes, when the bow of 
the arch will lie somewhat below the necks of the incisors. By spring- 
ing the front of the arch upward upon the necks of the incisor teeth 
and ligating them to the arch at the same time, an upward leverage 
will be exerted upon the second molar which will quickly restore it to 
an upright position, at the same time that it is being moved distally 
by the turning up of the nuts in front of the anchor tubes. 

Rotation of Molars.— Several methods are in use for the rotation 
of molars in torso-occlusion. In the rotation of a molar which has 



OPERATIVE TECHNIQUE. 



60 1 



its mesio-buccal cusp farther buccally than the disto-buccal cusp, 
the expansion arch, bent as at E in Fig. 425, before slipping into the 
buccal tube on the clamp band encircling the molar, answers every 
purpose, especially as the desired change of position of the molar 
is in line with the buccal movement of the expansion arch, the distal 
end traveling farther buccally than a point on the arch opposite the 
mesio-buccal cusp of the molar. 

The reverse of this position, or the molar with the mesio-buccal 
cusp farther lingual than the disto-buccal cusp, is not so amenable 
to change in the desired direction by the lingual bending of the ends 
of the expansion arch, since the tendency of the arch in its outward 




Fig. 438. 



movement is to move the disto-buccal cusp farther buccally in relation 
to the mesial cusp, in spite of the lingual bending of the arch to 
prevent it. 

A method devised by Dr. J. L. Young for effecting the rotation of 
the molar, is illustrated in Fig. 438, the two sides of the arch being 
treated slightly differently. 

On one-half of the arch, a clamp band, with its lingual screw 
directed distally, is fitted to the molar in torso-occlusion, and on that 
part of the band corresponding to the mesio-buccal angle, a short 
tube is soldered parallel to the long axis of the tooth, as shown in 
position on the clamp band on the right side of the cut. A short wire 
fitting into this tube snugly, is then soldered at right angles to the 
surface or to the end of an arch or tube. The attachment, when in 
position, forms a hinged anchor tube for the expansion arch at the 
mesio-buccal angle of the molar, as illustrated. 



e>o2 



ORTHODONTIA. 



The cuspid on the same side as the molar to be rotated is fitted 
with a band and a lingual hook pointing mesially, and a rubber 
band of sufficient strength attached from this hook to the lingual 
screw of the molar clamp band, as seen on lingual side of the arch 
in the figure. The cuspid should be firmly ligated to the arch 
so as to prevent its distal or rotary movement during the operation. 
When the nut on the expansion arch is tightened, the tendency to 
distal movement of the mesio-buccal angle of the molar, and the 
reciprocating action of the elastic, pulling the disto-lingual angle 
mesially, exerts the most positive rotating action upon the molar in 
the desired direction. 

A slight variation from this method is illustrated on the other 
side of the same arch on the left side of the cut. The expansion arch 




Fig. 439- 



Fig. 440. 



is attached to the mesio-buccal surface of the molar band by a ball 
and socket joint, allowing a little more freedom of movement of the 
molar in its rotary movement. 

A rigid hook is soldered to the expansion arch, curving between 
the cusps of the cuspid and first bicuspid on the same side of the arch, 
and extending up close to the palate, with the end of the hook pointing 
mesially. A rubber band of suitable strength is next attached from 
this hook over the lingual screw of the clamp band on the molar to be 
rotated as shown in the same cut. 

In this method, in which the attachments are all made to the 
expansion arch, the reciprocation of force is almost absolute from the 
mesio-buccal angle of the molar to the disto-lingual angle, in the 
rotary force exerted by the two opposite acting forces on each side. 

The Lever. — The principle of the lever is a very old one in its 
application to the dental arch, but there is no doubt that its use alone 



OPERATIVE TECHNIQUE. 603 

as a mechanical appliance for the correction of malocclusion is a mis- 
application of an efficient mechanical principle when properly used. 

For example, the old method of using the lever, Fig. 439, did not 
recognize the principle of arch expansion to make space for a rotated 
tooth before attempting to turn it into position. The fulcrum of the 
lever is at N, the weight at K, and the power at G-H. The two 
arrows, 1 and 2, indicate the direction of the turning tooth, and it will 
be seen that the arch becomes more contracted, if anything, during 
the process, the distance, E-F, from cuspid to cuspid remaining the 
same, thus preventing the alignment of the incisors, whose combined 
mesio-distal diameters are greater than the arc of the arch from one 
cuspid to the other. 

The proper use of the lever in this case should be as an auxiliary, 
the principle movements indicated being, first, general arch expansion, 
so that the incisors may have space for alignment; and second, rotation 
of individual teeth which are turned, as illustrated by the combination 
of expansion arch and lever in Fig. 440. 

By ligating the incisors and cuspids to the arch, at A, C, B, D, 
etc., the space for the lateral in torso-occlusion is j r 

gradually made, while the arch lever, L, at the same 
time is turning the tooth into position of correct align- 
ment. The arch lever may be made of German 
silver, or iridio-platinum, and should have a hook at 
one end to engage with the arch, so as to do away with tying it, Fig. 441. 

Operation for Abnormal Frenum Labium. — The separation 
of the upper central incisors through the abnormal lingual attachment 
of the frenum labium, extending, as it does, between the teeth to the 
lingual tuft in some cases, usually requires simple operative treatment 
beyond the movement of the two teeth together, and their retention 
for a considerable period, for, in the latter case, the presence of the 
frenum is still a causative factor in the return of the space between 
them. 

The plan of operative treatment usually followed, which was 
suggested by Dr. Angle, is that of splitting the ligament with a lancet, 
and cauterizing the wound with the actual cautery to obtain advantage 
of the cicatrization of the tissues which follows as well as by its inert- 
ness as an active force in causing separation of the teeth after they 
have been moved together. 

The author's method of treatment of these cases varies but slightly 
from that described, except that the frenum is as nearly as possible 
dissected from its attachment between the central incisors, by making 



604 



ORTHODONTIA. 



incisions upon either side of it, and cutting it off with a pair of gum 
scissors slightly above the necks of the incisors. 

The tissue is anesthetized as usual, and the teeth provided with 
cemented bands and spurs for the attachment of ligatures for drawing 
them together before performing the operation. 

After cutting out as much of the tough ligamentous attachment as 
is deemed necessary, the actual cautery is passed into the wound, 




Fig. 442. 



when it is allowed to heal for a couple of days, and then the two cen- 
trals are ligated together from the spurs upon the labial surface of 
their cemented bands. 

Their movement occupies but a short period of time, but even 
with the advantage of the shrinkage of the cicatricial tissue between 
them, their retention is a matter of a year's time even in the youngest 
The two central incisor bands are usually soldered together 



cases. 



and cemented in position for the retention of these cases. 

Fig. 442 illustrates the casts of a case of this character showing the 



OPERATIVE TECHNIQUE. 



60 ■ 



operation performed in this manner, the patient being eight years 
of age. 

Expansion of the Deciduous Arch. — Smaller molar clamp 
bands and a 17 or 18 gauge (B. & S.) expansion arch should be used 
for the expansion of the deciduous arch. Here the silk ligature 
covered with chloro-percha will be found especially useful, being 
much easier to adjust than the wire ligature. 

A valuable addition to operative technique in the lateral expansion 
of deciduous cuspids and molars is embodied in a suggestion of Dr. 
C. A. Hawley's, illustrated in Fig. 443. 

The clamp bands are reversed, with the lingual screws pointing 
distally, and lingual wires are soldered to their mesio-lingual angles, 




Fig. 443. (Hawley.) 



extending along the lingual surfaces of the deciduous molars, and 
ending in a hook opposite the deciduous cuspids, where one wire 
ligatured to the expansion arch on each side controls the lateral move- 
ment of all the deciduous teeth in each lateral half of the arch. 

Treatment of Infra-occlusion. — The most common form of 
infra-occlusion presenting in practice is that in which there is lack 
of occlusion of the anterior teeth, varying in degree from a slight 
infra-occlusion of one or more incisors to those cases in which the upper 
and lower incisors are more than half an inch apart when the molars 
are occluding. 

The simple cases of infra-occlusion of the incisors may be easily 
managed by bending the expansion arch downward before placing it in 
position, as in dotted lines in Fig. 444, and then springing it upward to 
ligate the incisors to it after it is in position. The incisors may be 
banded, with labial spurs for more direct application of the force. 
Further treatment of infra-occlusion is described under treatment of 
Class I and II. 



0O0 ORTHODONTIA. 

Early Treatment of Arrested Developmental Conditions in 
the Arches. — Any arrested or deficient development of the arches of 
teeth may be diagnosed in advance of the permanent dentition, and 
should be stimulated to normal growth and development as early 
as the age of the patient will allow the wearing of delicate arches and 
bands for the purpose. 

Except for mesial or distal occlusion of the deciduous arches of 
teeth, the arrested lateral development of the arch is a condition most 
commonly demanding interference by the orthodontist. 

The lack of mesial and distal spacing between the deciduous 
incisors and cuspids at about five or six years of age is a very certain 
indication of a lack of anterior development sufficient for the proper 
eruption of the permanent teeth succeeding them. 

If the deciduous arch needs widening, 
it is better to perform this operation some 
little time before the roots of the deciduous 
molars have begun to absorb, since the 
crowns of the permanent bicuspids are en- 
closed within the roots of the deciduous 
molars, as may be observed in Fig. 445, 
and the result of the expansion will be to 

move the crowns of these permanent teeth 
Fig. 444. r 

as well as the deciduous teeth and sur- 
rounding alveolar tissues into a larger arc, at the same time affording 
a gentle stimulus to the normal development of the arch. 

If treatment is delayed until just before the time for shedding 
of the deciduous first molars, the roots of these teeth being almost 
absorbed, can afford no resistance to the appliance in expansion, and 
the crown will be shed before any expansion can be accomplished in 
this region, which will then delay the widening of the arch in this region 
until the permanent bicuspids are fully erupted, there being no other 
means of anchorage in the meantime, except what may be possibly 
obtained through the ligation of the deciduous cuspid, which many 
times is prematurely shed. 

The author has obtained the best results in arch development 
between the ages of six and eight years, and in some cases still younger, 
especially where a mesial or distal occlusion seemed inevitable. 

It is reasonable to suppose, from the rapidity of development of 
the alveolar process during the primary stages of eruption of the 
permanent teeth, as illustrated in Fig. 446, that the movement of the 
deciduous teeth some little time previous to the period when absorption 




OPERATIVE TECHNIQUE. 



6o7 



of the roots of deciduous cuspids and molars is about to be initiated, 
conforms most nearly to a natural and physiological process, and 
that the amount of absorption of alveolar process in advance of moving 




Fig. 445. 



teeth is comparatively slight, the change in these structures being 
analagous to the natural developmental changes which would occur 
in case no arrest of development had been observed. 




Fig. 446. 

Ideal Treatment of a Practical Case. — Fig. 447 illustrates an 
arrested development of an upper arch of a child nine years of age, 
in which the deciduous cuspids and molars are still intact and firm 
in their positions, and capable of offering resistance to the appliance 



6o8 



ORTHODONTIA. 





e$9 


J<^\« 


Aw*' J 




Fig. 448. 



OPERATIVE TECHNIQUE. 609 

for lateral expansion of the arch, and of carrying with them the crowns 
of the permanent bicuspids, and surrounding alveolar structures. 

Although the permanent central incisors and first molars have 
erupted, as far as development is concerned, it is still a deciduous 
arch, and the diagram for a .39 central indicates that considerable 
anterior and posterior expansion is necessary at this time in order 
to secure sufficient development for the accommodation of the perma- 
nent teeth yet to erupt. 

The result of treatment of this arch, according to these indications, 
is exhibited in Fig. 448, in which the extent of the development is 
measured by the diagram of the pre-determined arch. 

Further development of this arch can safely be entrusted to nature, 
provided that the amount of development already obtained is effect- 
ually retained as long as possible before the eruption of the permanent 
cuspids and bicuspids. The retention of this arch is illustrated in 
Fig. 575, in the chapter on retention, the deciduous teeth being utilized 
for resistance until such time as the absorption of their roots would 
render them unfit for such use. 

Realizing the benefits of such early development of the dental 
arches, the orthodontia specialist prefers to operate upon the chil- 
dren in whose mouths, the presence of firmly implanted deciduous teeth 
offer resistance for development of the dental arch in advance of the 
eruption of the majority of the permanent teeth. In the last decade, 
the personnel of the specialist's practice has gradually changed from 
the adult to the child, with consequent greater possibilities of per- 
manent benefit to the individual. 

Advantages of Early Treatment. — Briefly detailed, the advant- 
ages of early treatment of malocclusion and arrested development of 
the dental arches are as follows : 

1. Early treatment is undertaken at a time when the alveolar 
processes are more cartilaginous in character than later, the teeth being 
thus more readily moved because of lessened resistance than when the 
cartilaginous structures are fully calcified. 

2. The restoration of the proper size and shape of the arches at 
an early age conforms more nearly to a physiological process or a 
stimulation to normal development, rather than a tearing down and 
rebuilding process which would be necessary at a mature age. 

3. The function of the dental arches being restored early in child 
life, all developmental processes in relation thereto, such as the growth 
of the dental and maxillary arches and the nasal cavities, and the 
conformation of the muscles of mastication and expression, will have 

39 



01 ORTHODONTIA. 

the best chance for normal development, and the attainment of 
harmony in the profile become a possibility through such normal 
relationships. 

4. The earlier treatment is undertaken, the less tendency exists 
for the return of the malocclusion, and the less the need of retention, 
as age only increases resistance to tooth movement, confirms the 
deformity in its relationship by long and improper function of occlusion 
and muscular expression, and by the initiation of structural changes 
in bony and muscular tissues which cannot be removed by treatment. 

VII. CLASS-I-TREATMENT. 

Etiology and Diagnosis. — In the first class of malocclusion, the 
teeth may be in any possible position of abnormality which would be 
consistent with a normal antero-posterior relationship of the arches of 
teeth. For example, any of the incisors and canines may be in labial 
or lingual occlusion, or the bicuspids and molars in buccal or lingual 
occlusion. There may be protrusions of the anterior part of the upper 
arch, or retrusions of the anterior part of the lower arch, without dis- 
turbing the normal antero-posterior relationship in the molar region. 

The etiological manifestations and the variations in harmony in 
the facial profile are more varied than in any other class, and, taken 
together with the multiplicity of malpositions of the teeth, often 
simulating in general appearance the malocclusions of the other classes, 
make it the most misleading in its characteristics and difficult in its 
diagnosis. 

The mouth-breather is not infrequently seen in this class of mal- 
occlusion, presenting many times a simulation of the mouth-breather 
of Class II, with protruding upper incisors, or a lack of anterior 
occlusion. 

Among the etiological characteristics noted in this class are the 
prolonged retention of deciduous teeth, the premature loss of deciduous 
teeth, loss of permanent teeth, supernumeraries, abnormal frenum 
labium, lip-biting and thumb-sucking, and mouth-breathing. 

Malnutrition, through the diminution of a proper lymph or blood 
supply, is responsible to a large extent for the undeveloped arches of 
teeth, which are chiefly noticeable in the class under consideration. 

The diagnosis of this class is indicated by the normal mesio-distal 
relation of the first molars, which, having been determined, by noting 
the proper occlusion of first molar cusps on either side, renders the 
indications for treatment a restoration of the normal relationship 
of occlusal conditions anterior to the first molars, except in so far as 



CLASS-I-TREATMENT. 



6ll 



the lateral expansion of both arches may effect the bucco-lingual 
relations of these teeth. 

Anchorage Requirements. — A study of the case should next be 
made with reference to the form and requirements of anchorage, having 




Fig. 449. 

in mind that a combination of a number of different forms of anchorage 
may be necessary in the treatment of this class of cases, even to the 
extent of using a form of anchorage especially required for either Class 
II or III in certain cases. 




Fig. 45°- 



A pre-determination of the size of the completed arch by the method 
of arch determination previously described in the chapter on diagnosis, 
will aid in the plan for lateral expansion, indicating the size of the 
arc of the anterior portion of the expansion arch, and the alignment 
of the anchor tubes on molar bands to suit the case. 



6l2 ORTHODONTIA. 

Extraction, as a beneficial procedure, should be excluded except 
in rare cases, and where it has already been resorted to, the restoration 
of lost space through contraction at the point of extraction, should 
be accomplished and retained by proper methods. 

Symptoms of mouth-breathing should be immediately noted, and 




Fig. 451. 

the case referred to a competent rhinologist for examination of the 
nose and throat, and removal of nasal or pharyngeal obstruction if 
found present. 

Treatment of Special Cases. — Fig. 449 represents the right occlu- 
sion, before and after treatment, of an average case of Class I, the 




Fig. 452. 

arches being contracted and the teeth anterior to the first molars .'in 
various positions of malocclusion previous to treatment, and after- 
ward in normal occlusal relation, as noted in the model on the right 
of this figure. 

The left occlusion, in Fig. 450, illustrates the movement of the 




CLASS-I-TREATMENT. 613 

upper left central from lingual to normal occlusion, and the regaining 
of the proper space for, and eruption to normal position of the left 
lower second bicuspid. 

Fig. 451 exhibits the restoration of the normal size and shape of 
the upper arch, the malposed teeth being placed in the line of occlu- 
sion, as noted in the cast on the right of the cut. 

Fig. 452 presents the chief difficulties encountered in the case, 
in the extent of the contraction of the anterior portion of the lower 
arch and the attainment of the ideal in the size and shape of the arch 
as a final result. The lower unerupted bicuspid very quickly took 
advantage of its release from imprisonment between the first bi- 
cuspid and first molar, and erupted into 
occlusion without mechanical aid, lending 
its additional support as a keystone to 
hold the arch intact. The presence of 
the unerupted bicuspid in the process 
could be diagnosed by the swollen con- 
dition of the gum tissue overlying the 
tooth, without the use of the X-ray as is 

r i Fig. 453. 

otten necessary in these cases. 

The appliances used in this case are the expansion arch and 
anchor clamp bands. In the upper arch, the left central was banded, 
and the ligature extended from a lingual spur to the arch, with the 
rubber wedge between the mesial angle of the tooth and the arch to 
assist in its rotation. Very little expansion was needed in the upper 
arch beyond that necessary for the accommodation of the left central. 

In the lower arch considerable lateral expansion was necessary, 
and the adjustment of the appliances so as to obtain reciprocal anchor- 
age from one side of the arch to the other through ligatures on the 
arch. The left lower first bicuspid was banded, and a ligature extended 
from a mesio-lingual lug on the band to a spur on the arch wire, so 
as to secure the two necessary movements of rotation and lateral 
realignment of this tooth. 

The retention of the upper arch consisted of a single band upon 
the left central, with a distal spur extending over and touching the 
labial surface of the left lateral, which was worn for a few months 
only, as the occlusal inclined plane of the lower central and lateral 
incisors on that side effectually retained the central in position after 
that time. 

The retention of the lower arch in this case, as seen in Fig. 453, 
was somewhat more complicated than the upper, yet the least number 



6i 4 



ORTHODONTIA. 



of bands upon individual teeth that would meet the requirements of 
retention were used. The bands on each cuspid, united by a lingual 
wire, and having lingual wire extensions upon the surfaces of the first 




Fig. 454- 




Fig. 455. 



bicuspids, served to retain the lateral expansion of the arch as well 
as the alignment of the six anterior teeth. The extra band with labial 
spur on the first bicuspid on the left side was placed there to prevent 



CLASS-I-TREATMENT. 615 

torsion of this tooth. The author has found it advisable to retain 
individual teeth which have been rotated to any extent, with single 
band and properly placed spurs, when they can not be advantageously 
banded in the construction of the general retaining apparatus. 

The case just illustrated, although presenting some difficulties 
in the treatment of the lower arch, is simple compared with the prob- 
lems of normal arch and occlusal restoration exhibited in the treatment 
of the next case, the right occlusion, before and after treatment of 
which is shown in Fig. 454. 

The case is that of a boy fourteen years of age, and in the model 
on the left of Fig. 454 may be noted the contracted arch, and the closing 
up of the space for the upper second bicuspid and the partial closure of 
the space for the lower bicuspids, which are impacted in the alveolus 
just external to their positions in the arch. 

The etiological factors in this case were obscure, in that the 
boy was a normal breather, of good history, and, beyond the pre- 
mature loss of the deciduous cuspids and molars, as a mechanical 
factor in the causation of the undeveloped arches, very little could be 
learned of a pathological nature which might have affected the nor- 
mal development of the dental arches. 

The occlusal view of the upper casts, before and after treatment, 
in Fig. 455, exhibits a degree of expansion which would not have been 
believed possible by the uninitiated in the secrets of occlusal restoration. 
The upper second bicuspid on the right side was freed from impaction, 
and erupted to its proper position of occlusion, the cuspids also being 
restored to alignment, or rather the rest of the teeth in the anterior 
part of the arch to the cuspid alignment, as they were more nearly 
in their normal positions than any of the other anterior teeth. 

The lower cast on the left of Fig. 456 exhibits the impaction of 
three teeth, two bicuspids on the right side and the second bicuspid 
on the left side, the release of which could never have been possible 
without the interference of the orthodontist. In the cast on the right, 
the successful accomplishment of the necessary expansion for the 
accommodation of these teeth in the arch may be noted. By com- 
parison of the before and after casts of both upper and lower arches 
in this case, the unusual amount of lateral expansion may be observed, 
showing how far short nature came in her development of the arches, 
and the possibilities of applied science in the restoration of the normal 
in development and the ideal in occlusion and harmony of contour 
of the arches of teeth. 

The picture of the left occlusion of the case before and after treat- 



6i6 



ORTHODONTIA. 



ment, in Fig. 457, needs no description. The result of ideally correct 
treatment without extraction is verv evident, and the classic lines in 




Fig. 456. 







Fig. 457- 



the after-treatment model can scarcely be excelled in beauty by any 
masterpiece of the sculptor's art. Notice the graceful curves of the 
arches, the symmetry and proportion of contour, the wonderful har- 



CLASS-I-TREATMENT. 



617 



mony which prevails in the arches through the perfect adjustment of 
each occlusal inclined plane of the antagonizing teeth to the require- 
ments of normal occlusion. 

The accompanying profile of this patient in Fig. 458 is shown to 
illustrate the fact that such an extensive operation of expansion of 
arches does not produce undue protrusion, as has been commonly 
supposed. The lower part of the face is entirely in harmony with the 
rest of the features, being proportionate for its type, and in its contour 
hardly suggestive that an operation of this extent had been performed 
upon the dental arches. 

The appliances used in this case 
were similar to those in the previous 
case, and the treatment only differed 
in its extent of expansion carried out, 
and the opening of the greater number 
of spaces necessary for the accommo- 
dation of the teeth which were either 
partially or wholly unerupted. 

Soldered spurs upon the arches 
guided the direction of the ligatures 
upon teeth contiguous to the spaces 
to be opened, some of which it was 
necessary to band, and provide with 
lingual spurs for the most positive 
action of the appliance to be exerted 
upon them. FlG - 45 8 - 

In the upper arch, the lateral in- 
cisors and right first bicuspid were banded and ligated to the expansion 
arch from spurs attached to their disto-lingual angles. 

In the lower arch, the teeth needing banding in a similar manner 
were the right cuspid and the left first bicuspid, as a most positive 
attachment of ligatures was necessary in order to reopen the adjacent 
spaces for the unerupted teeth. 

The upper arch was retained anteriorly by uniting cuspid bands 
with a lingual wire, and posteriorly by a roofplate, Fig. 459. 

The lower arch was retained anteriorly by a lingua) wire attached 
to cuspid bands, from which spurs were extended to include the first 
bicuspids, Fig. 460. 

A very interesting case of Class I in the peculiarity of its maloc- 
clusion, and in the combination of appliances and anchorage nec- 
essary for its treatment, is illustrated from the occlusal aspect of the 




6i8 



ORTHODONTIA. 



upper arch before treatment in Fig. 461, the feature of particular 
interest being the disto-lingual position of the upper right cuspid, 
which, on account of its extreme distal position opposite the inter- 
proximate space between the two bicuspids, is apparently secure in 
its malocclusion, presenting unusual obstacles to its restoration to the 
line of occlusion. 

By a careful conservation of anchorage and operation of the 
appliances, the accomplishment of the desired result, as shown in the 
after-treatment cast of the upper arch in Fig. 462, was secured. 

The primary anchorage and its usual re-enforcements by ligatures 
for expansion of the arch, is entirely inadequate to produce the desired 
results in a case of this kind, for although the space for the right cuspid 




Fig. 459. 



Fig. 460. 



could be regained by a proper direction of ligatures on the expansion 
arch, the control of the cuspid in lingual occlusion in this same manner 
is impracticable. 

The cuspid needed first to be moved forward opposite its regained 
space by means of a traction screw operating from the first molar 
anchorage, being attached to the lingual screw, as seen in Fig. 463, 
the right angled end operating in a horizontal tube soldered to the 
mesial surface of a band upon the cuspid. 

The expansion arch w T as in operation at the same time enlarging 
the arch and making room for the cuspid, the incisors being directed 
toward the opposite side of the arch by spurs located toward the left 
side of the arch from each incisor, and the right lateral having a band 
with a lingual spur for more positive action of the ligature at this point. 

It is evident that the combined distally reacting forces of the ex- 
pansion arch on the buccal, and the traction screw on the lingual side 
of the first molar, would be greater than the resistance of the first 
molar without re-enforcement, and the use of intermaxillary anchorage 



CLASS-I-TREATMENT. 



619 




Fig 461 




Fig. 462. 



(V20 



ORTHODONTIA. 



for this purpose as illustrated in Fig. 464 effectually counterbalanced 
the tendency to distal movement of the molar, so that the forces acting 
mesially from this base could operate without disturbing the stability 
of the anchorage. 

The operation on the lower arch was comparatively simple, re- 
quiring lateral and anterior expansion to harmonize the occlusion with 
that of the upper arch, at the same time regaining the full space for 







Fig. 463- 



the lower right first molar, part of the mesio-distal diameter of which 
has been lost through caries. 

The success of this combination of appliances may be noted in the 
right occlusion, before and after treatment, in Figs. 465 and 466, the 
cuspid occupying its normal position in the arch, and the occlusion 
of both arches being restored to harmonious cusp relationship. 

Infra-occlusion of Incisors and Cuspids. — Lack of occlusion of 
the incisors and cuspids and often of the bicuspids is a condition not 
uncommonly found, usually in mouth-breathers, and varying in extent 
somewhat according to the aggravation of the habit. It occurs in all 
classes of malocclusion, and because of the less number of compli- 



CLASS-I-TREATMENT. 



62 



cations it presents in Class I, it responds more readily to treatment 
than in the other classes. 

As this condition is essentially a lack of development of the pre- 
maxillary portion of the arches, and an abnormal development, in many 
cases, of the posterior part of the arches, cases presenting infra-occlusion 




Fig. 464. 

of the anterior teeth should be treated as early as possible, and especially 
normal habits of breathing restored at the same time so that develop- 
ment may be further unimpeded by any nasal or other respiratory 
obstruction. 

Fig. 467 represents a case of this class in a mouth-breather eight 
years of age, before and after treatment. 



02 2 



ORTHODONTIA. 




Fig. 465. 




Fig. 466. 



CLASS-I-TREATMENT. 



623 



After removal of adenoids by a rhinologist, expansion arches were 
placed upon each arch, the incisors all banded, with spurs well up to- 




Fig. 467 




Fig. 467 a. 

ward the gingivae, to which wire ligatures were attached from the 
anterior part of the arches, which were bent downward towards the 



024 



ORTHODONTIA. 



incisal edges so as to afford a downward spring on the upper, and an 
upward spring on the lower arch when ligated, as in Fig. 444, chapter 
on operative technique. 

The retention of this case was effected by means of a lingual arch 
on the upper, Fig. 578, soldered to the ends of the lingual screws on anchor 
clamp bands fitted to the deciduous molars, the front of the arch en- 
gaging with lingual spurs on the incisors, and re-inforced by spurs ex- 
tending over the occlusal surface of the first deciduous molars, the in- 
cisors being thus prevented from going back into their sockets. This 
retention was worn for about two years, until sufficient development 
in the premaxillary region had taken place. The retention of the 
lower arch was very similar to that of the upper. Cases of greater 




Fig. 468. 
severity are not as simply treated as this one just described, the use of 
intermaxillary anchorage from the anterior part of each arch being 
required in order to overcome the greater resistance encountered, as 
illustrated in Fig. 511, chapter on treatment of Class II. 

Fig. 468 illustrates a case of infra-occlusion of this class, from the 
practice of Dr. L. S. Lourie, and represents as near the ideal in 
treatment of these conditions as it is possible to attain. 

After the age of development has passed, the difficulties attendant 
upon retaining the teeth in occlusion, even though the operation might 
be otherwise possible and feasible, render it advisable in many cases 
to perform the simpler operation of extensive grinding of the molars 
and bicuspids until occlusion is obtained, even if the vitality of one or 
more of the molars may have to be sacrificed in so doing. 

The author has derived a great deal of satisfaction from this proce- 
dure in cases of adults, observing, however, great care that a certain 
amount of cusp articulation is preserved in order that the function of 
articulation and mastication may not be interfered with. In other words, 



CLASS-I-TREATMENT. 



625 




Fig 469. 




40 



Fig 470. 



626 



ORTHODONTIA. 




FrG 471. 




Fig. 472. 



CLASS-I-TREATMENT. 627 

the molars should not be ground off flat, but grooved for cusps as in grind- 
ing artificial teeth for articulation. The operation is a difficult one, 
in that it requires the greatest care not to grind too much upon certain 
teeth and not enough upon others. Occlusal contact points should be 
ground a little at a time, on one side of the arch and then upon the other, 
approximating the arches of teeth only a limited amount at each of 
several sittings until occlusion is obtained. 

The shortness of the lips in these cases, especially the upper, is such 
as to preclude the idea of elongation of the incisors to occlusion, an 
unnatural length being unesthetic. 

Infra-occlusion of Molars and Bicuspids.— Figs. 469 and 471 
illustrate a Class I case of infra-occlusion of. the molars and bicuspids 
from the practice of Dr. F. C. Kemple. This condition is a very un- 
usual one, presenting as it does, with the incisor region in perfect normal 
occlusal relations and an entire lack of occlusion from the cuspid 
to the second molars on each side. The patient was fifteen years of age 
and the function of mastication was limited to the six anterior teeth, 
in each arch. Such peculiarities of abnormal development are hard to 
explain, yet the fact that they exist ought to bring to bear a much closer 
study of the underlying factors in development which produced 
them. 

In the treatment of this case Fig. 473 expansion arches were ad- 
justed to each arch, using the first molars as a primary anchorage for the 
clamp bands, banding the eight bicuspids, with spur extensions over the 
expansion arches above and below, and allowing the incisors and cus- 
pids to remain free from ligation, as they were not to share in the move- 
ments to be undertaken. 

Intermaxillary elastics were then adjusted between spurs on tubes 
of the molar clamp bands and from each expansion arch in the region 
of the first bicuspids. 

The after-treatment models of the case are shown in Figs. 470 and 
472, showing the molars and bicuspids have been drawn into occlusion 
with each other, and a very successful result obtained. The retention 
consisted of a continuation of the use of the intermaxillary force in 
connection with a more delicate and inconspicuous appliance for an 
indefinite period. 

Use and Limitations of the Removable Appliance.— The 
author advocates the use of the removable appliances with the spring 
clasp attachments for anchorage only in the simpler cases of maloc- 
clusion. 
The multiplicity of finger springs in the Jackson spring clasp appliances 



628 



ORTHODONTIA. 



when used in a complicated case where a great many individual tooth 
movements are required, is contrary to the law of simplicity in con- 
struction and operation of appliances, and the use of intermaxillary 
elastics in connection with upper and lower spring clasp appliances in 
Class II and III cases is of doubtful practicability, owing to the insta- 
bility of the anchorage, and to the lack of control of the individual teeth 
in each arch, as compared to the use of the expansion arch and molar 
bands in the same cases. 




Fig. 473- 



As an example of its consistent use in the treatment of a simple 
case of Class I, the spring clasp appliance shown in Fig. 474 is a fair 
specimen. It will be observed that but two teeth, the upper lateral 
incisors, are the objective of the finger springs of the appliance, and 
that there is sufficient space for the accommodation of these teeth in 
the arch. 

The front view of this case, before and after treatment, is illus- 
trated in Fig. 475, the operation having been accomplished in a few 
days, with no inconvenience nor discomfort. If properly made, the 
anchorage of the spring clasps and partial spring clasps is sufficiently 
stable for performing certain tooth movements, and the possibility of 



CLASS-I-TREATMENT. 



629 



removal by the patient is so infrequent in practice as to not seriously 

discourage the operator to make use of these appliances on this account. 

In cases where teeth are out of the line of occlusion, in contracted 

arches, the removable spring clasp appliance is not the simplest in 




Fig. 474- 

construction nor operation, nor is it efficient in comparison with a fixed 
appliance of the nature of the buccal expansion arch anchored to molar 
clamp bands. 

Protrusions of Class I. — Fig. 476 illustrates an upper protrusion 
of Class I, which was treated by the use of intermaxillary anchorage, 




Fig. 475- 



allowing the upper expansion arch to be free in its distal movement by 
loosening the nut in front of the anchor tubes, so that all of the pressure 
from the intermaxillary force could be exerted against the labial sur- 
face of the upper incisors. At the same time, the ligation of the in- 



630 



ORTHODONTIA. 



cisorSj cuspids and bicuspids to the arch assisted in restoring the normal 
line of occlusion. 

An interesting feature of this case was a comparative test in the 
methods of treatment between a Jackson removable appliance with 




Fig. 476. 

spring clasp attachments, as shown in Fig. 477, in position on the up- 
per arch after completion, where it was finally used as a retainer, and 
the expansion arches in combination for the utilization of intermaxillary 




Fig. 477- 



force in reducing the protrusion and restoring the normal occlusal re- 
lations of the anterior teeth. 

The treatment with the removable appliance was inaugurated first, 
with the result that although the incisors were easily retruded up to a 



CLASS-I-TREATMENT. 



63I 



certain point, the ineffectiveness of this appliance for completion of 
the case was distinctly noticeable, in that it had the effect of crowding 
the incisors together, or •'buckling" them, with no remedy with except 
the possible making of a new appliance of the same pattern with a 
number of finger springs attached to overcome these tendencies, with 
the possibility of other changes in position of the individual teeth which 
might not be under control of these springs. 

The application of the expansion arches, and the utilization of in- 
termaxillary force and anchorage at this stage immediately alleviated 
all of the difficulties met with in the previous method of treatment 
and brought the case through to a successful completion. 

The expansion arches in position (on the casts) with the inter- 
maxillary elastic stretched from the distal end of the buccal tube on the 
lower molar clamp bands to the 
hooks on the upper expansion arch 
are illustrated in the drawing in 
Fig. 478. 

The resistance of the entire 
lower arch was enlisted by ligating 
all of the eight anterior teeth to the 
lower expansion arch, allowing the 
nuts to be unused except occasion- 
ally for slightly increasing the 
tension of the expansion arch to 
slightly widen the anterior portion 
of the lower arch. 

By allowing the expansion arch to slide distally in the anchor tubes 
on upper molar clamp bands, all of the intermaxillary force was directed 
against the labial surface of the incisors, and by the use of ligatures in 
proper places, lateral expansion in the cuspid region was instituted, and 
the normal occlusion of the anterior teeth restored. 

A similar protrusion of Class I to that just described but of greater 
severity, is illustrated in Figs. 479 and 480, before and after treatment. 

In addition to the protrusion of the upper incisors, the lower arch 
was contracted in the region of the second bicuspid which was une- 
rupted, and its space in the arch considerably diminished on account 
of the early loss of the second deciduous molar. 

Exactly the same method was used for reducing the anterior upper 
protrusion as in the previous case, at the same time enlarging the lower 
arch and regaining the space for the unerupted bicuspid. 

In the retention of the upper arch, a retaining plate similar to the 




632 ORTHODONTIA. 

one used in the previous case was worn for three years, after which 
time no tendency to the return of the protrusion was apparent. 

The lower arch needed retention only in the region of the unerupted 
bicuspids, and this was accomplished by bands upon molar and first 




Fie. 479. 

bicuspid on either side united by a soldered spur on the buccal surface, 
the bands being firmly cemented in position. The failure of the bicus- 
pids to erupt after three years' retention required permanent bridge- 
work for further retention of this space on either side, and the family 




Fig. 480. 



dentist constructed a permanent all gold denture on each side sup- 
ported by the molar and first bicuspid as abutments. 

The patient had been a mouth-breather in early childhood, but had 
been operated upon for the removal of adenoids early enough so that 



CLASS-I-TREATMENT. 



6 33 



through the restoration of the normal in occlusal relations of the arches 
of teeth, the asymmetry of the facial lines was completely overcome, 
as is evidenced from the photographs of the profile in Figs. 481 and 





Fig. 481. 



Fig. 482. 



482. The asymmetry of the facial lines in this case is so similar to 
the most severe types of the first division of Class II, that a differential 
diagnosis cannot be made without a diagnosis of the cusp relationship 
of the arches of teeth in occlusion. 




Fig. 483- 

Fig. 483 illustrates a not uncommon case of this class in which the 
characteristics of Class III are simulated in the apparent protrusion 
of the lower arch, and the inharmony of the facial lines. 



°34 



ORTHODONTIA. 



In the treatment of this case, anterior expansion of the upper arch 
alone was necessary, with bands upon the lateral incisors, and ligatures 
so directed and manipulated that the space for the unerupted cuspids 
was regained, after which a lingual retaining plate was used for reten- 
tion, a buccal spur extending through the cuspid spaces. 

The profiles of this patient, before and after treatment, in Figs. 484 
and 485, show the result of the treatment in restoring harmony to the 
face, and contrasts the error of diagnosis from the facial lines alone, as 





Fig. 484- 



Fig. 485. 



a casual observance of the profile alone would indicate a protrusion of 
the lower arch characteristic of Class III. 

An unusually complicated malocclusion of Class I, the correction 
of which was successfully completed by Dr. M. T. Watson by the use of 
a unique appliance, is illustrated in Fig. 486 before treatment. The re- 
quirements of treatment were that the upper arch should be expanded 
on the left side, and the lower arch on the right side, and the use of the 
expansion arches in the ordinary way would have been impracticable. 

Clamp bands were fitted to the upper left first molar, and first 



CLASS-I-TREATMENT. 



635 




Fig. 486. 




Fig 487- 



636 ORTHODONTIA. 

bicuspid, to the buccal surfaces of which was soldered a rigid iridio- 
platinum wire, bent as shown in Fig. 487. 

The lingual screws of these clamp bands engaged the lingual sur- 
face of the upper second bicuspid, so that the three teeth must move, 
buccally en masse, on application of lateral expansive force. 

The lower right second bicuspid, which was itself in lingual occlu- 
sion, was used as base of anchorage for a lower expansion arch, which 
slipped into the buccal tube of a clamp band upon the bicuspid, and, 
extending around to the left side of the mouth, engaged with the upper 
appliance by means of a stiff upright bar of iridio-platinum, this latter 
having first been hard soldered to a short section of German silver 
tubing, which, in turn, was soft soldered to the expansion arch. 

Bending the expansion arch so as to give it the greatest amount of 
lateral spring, the tendency of the appliance was to force the three up- 
per teeth buccally, and to bring the lower right second bicuspid into 
line.* 

A few weeks' wearing of this appliance restored the normal bucco- 
lingual relations on both sides, so that the case could be finished by 
the substitution of the expansion arches, and the treatment carried on 
in the usual way. 

TREATMENT— CLASS II. 

Etiology and Diagnosis of Class II. — The distinguishing charac- 
teristic of Class II in occlusal relations, is the bilateral or unilateral 
distal occlusion of the lower arch, the upper arch being narrow with 
protruding incisors in the first division, and retruded incisors in the 
second division. 

The facial profile is deficient in contour in such a way as to be 
indicative of the malocclusion, the chin and lower lip receding, and 
the upper lip protruding, in the first division of this class, as illustrated 
in Fig. 500. 

In the second division, a marked recession of both upper and lower 
lips and chin is noticeable, as in Fig. 523. 

The habit of mouth-breathing, and the open and drooping mouth, 
the short upper lip, the receding chin and the facial expression, are 
peculiarly diagnostic of the first division of Class II, although it is 

* A slight modification of this appliance was successfully used by Doctors Hoff and 
Burrill, on a little patient less than five years old who had lost a section of the lower jaw, 
extending from the cuspid region on the right, around to the ramus on the left. The re- 
maining portion of the mandible on the right side, had become so much displaced as to 
be biting completely inside the upper teeth. Considerable difficulty was experienced in 
securely fastening the appliances to the deciduous teeth, but that was finally overcome, 
and occlusion established on that side of the mouth where teeth were present. 



TREATMENT — CLASS II. 637 

sometimes difficult to distinguish it from the mouth-breather of Class 
I by observance of the facial inharmony alone. 

The presence of adenoids and enlarged tonsils is sufficient evi- 
dence of the causative factors underlying the mouth-breathing, which 
should receive early operative treatment by the rhinologist. 

The study of the possible etiology of the particular malocclusion 
manifested in Class II cases is important to the diagnostician, as upon 
his ability to recognize the chief causative factors present in these con- 
ditions rests his success or failure in their treatment. 

Following the history of this class of cases to a period when certain 
arrested developmental conditions were inaugurated, it may be stated 
that consecutively, arrest of development first occurred in one or both 




Fig. 488. 

of the dental arches, and secondly, the later growth of the dental arches 
was along abnormal lines influenced by such factors as malocclusion 
of the inclined cusp planes, and in many cases by the habit of mouth- 
breathing, with its abnormal tension of muscles. 

In a careful study of these conditions, the author believes that 
there is a predisposition to the malformation of dental arches and the 
distal occlusion in these cases long before the eruption of the per- 
manent teeth to occlusion. 

It has been stated by Dr. Angle that many cases of distal occlusion 
owe their inception to the abnormal influence of the inclined cusp 
planes of the first permanent molars in erupting, the exact period 
of their departure into the abnormal or distal occlusion being within 
a very short period after the touching of antagonizing cusps of these 
teeth. (See Angle — Malocclusion of the Teeth, seventh edition — 
pages 115, 116, 449, 454, Par. 3.) 

The existence of distal occlusion of the deciduous arches ought to 
contradict this theory, in whole or in part, since certain persistent 



638 ORTHODONTIA. 

factors other than any cusp influence must have been pre-operative 
in establishing these conditions in the deciduous arches. 

That distal occlusion is not uncommon among children of less 
than six years of age is a fact which the model cabinets of the specialist 
in orthodontia can easily prove. 

Treatment of these conditions of distal occlusion in the deciduous 
arches is established upon the same basis of normal restoration of 
occlusion and development as with the dental arches which contain 
at least rthe four permanent molars of the second dentition. 




Fig. 489. 

Figs. 488 and 489 illustrate a distal occlusion and facial profile of 
a child, two years and ten months old. 

Not only is the distal occlusion of considerable extent, but the 
facial inharmony easily noticeable at this age. 

It is the author's opinion that the large majority of cases of distal 
occlusions are initiated during the retention of the deciduous teeth, 
and the impress of arrested function and growth so made upon the 
developing structures of the maxillae, that none but artificial stimulus 
could again restore the normal in developmental conditions. 

It is possible that holding the mouth open in mouth-breathing 



TREATMENT — CLASS II. 639 

gives the mandible its distal pose in these cases, and it is certain that 
in those cases of Class II, Div. i, presenting the shortened upper lip, 
the abnormal tension of the muscles is an etiological factor in the 
narrowing of the upper arch, which latter is, of itself, an effectual 
barrier to a forward pose of the mandible. 

In the treatment of certain cases of Class II, Div. i, it has been 
not infrequently observed that after a sufficient expansion of the upper 
dental arch, especially in children under ten years of age, the mandible 
moves forward of its own volition until the first molars are in correct 
mesio-distal relations. 

Recognizing the possibility of arrested or deficient development 
of the maxillary arches being primarily due to such a general cause 
as malnutrition, or as caused by such local conditions as nasal stenosis 
and mouth-breathing, it will be admitted that the time the interference 
with development occurs will bear a certain definite relation to the 
period of deficiency in local associated functions of the oral and nasal 
cavities or of the general nutritive functions. 

Dr Ottolengui very aptly states this theory in the following manner : 
"Malnutrition is the special cause of malocclusions of Classes II 
and III. The permanent teeth do not displace those of the primary 
set, but erupt into a larger, and what is more important, an entirely 
different arch, and the bony process is a new bone built about them 
during their eruption. Grant this hypothesis, and it is evident at once, 
that if, during this period of transformation, there be an interference 
with normal functions, there may and probably will be a lack of bone 
building nutriment. What will result? The permanent teeth, all 
larger than their predecessors, erupt into the same small arch which 
the temporary teeth had occupied, or into one insufficiently enlarged, 
because of insufficient nutritive elements." 

"Thus the consequent malocclusion oj the teeth will be in nature and 
degree constantly related to the extent and time of the disturbance in nutri- 
tional fundi oning. ' ' * 

Intermaxillary anchorage is secured by the attachment of the rub- 
ber ligatures from the hooks on the upper expansion arch to the ends of 
the tubes on the lower expansion arch, as illustrated in Fig. 490. In 
simple cases of this class the first permanent molars may be used for 
attachment of clamp bands in case the second molars are erupted, 
since the intermaxillary force can be made strong enough to move 
the upper molars distally and the lower molars mesially. 

* Ottolengui, " A Contribution to the Etiology and Treatment of Class II " Transac- 
tions of the American Society of Osthodontists, 1907. 



040 



ORTHODONTIA. 




Fig. 490. 



In extreme cases of this class, however, and especially those in 
which it is desired to move the upper molars distally, to any extent, the 
clamp bands should be placed on the upper second molars and shifted 
to first molars as soon as desired movement of second molars has been 
accomplished. During the use of intermaxillary force for shifting the 

molar occlusion, the front of 
the upper expansion arch 
should be kept free from the 
anterior teeth by tightening 
up the nut in front of the an- 
chor tubes so as to apply the 
greatest amount of force di- 
rectly to the molar teeth. 

In the more severe cases 
of the first division of Class 
II, it will be necessary to re- 
move the clamp bands from 
the upper first molars and 
place clamp bands on the upper second and even first bicuspids in 
succession for support of the expansion arch and further shifting of 
the occlusion in the bicuspid region. 

The strength of the intermaxillary force can be increased by using 
a heavier ligature or a number of the same size, cut from French tubing. 
While these manipulations of 
anchor bands ■ and expansion 
arches are being carried on in 
the upper arch, the entire lower 
arch may be used part of the 
time as resistance for the shift- 
ing of the upper molar occlusion, 
by the ligation of a sufficient 
number of teeth to the lower arch 
to insure its stability. 

Again the lower incisors may 
be ligated to the expansion arch 
and moved forward, and suc- 
cessively, also, the cuspids and the bicuspids, to secure direct appli- 
cation of the force from the turning up of the nut in front of the 
lower anchor clamp bands, these teeth, in turn, being moved mesially 
by the intermaxillary force. 

There is one very important detail in the manipulation of this 




Fig. 491. 



TREATMENT — CLASS II. 641 

anchorage in Class II and III cases which ought to be described in this 
connection, and that is the tipping backward of the upper molars in 
Class II, and the lower molars in Class III — and the tipping forward 
of the lower molars in Class II, and the upper molars in Class III — 
which in turn shifts the expansion arch upward or downward, as the 
case may be. 

To remedy this, and keep up the efficiency of the anchorage, the 
clamp bands should be removed and the angle of the inclination of the 
tubes changed according to the necessities of the case and the class. 
Fig. 598 A exhibits the tipping of upper molars and downward inclina- 
tion of the expansion arch in a case of Class II, and B the restora- 
tion of the arch to position after realigning of the tube on molar clamp 
band. The technique of this operation is described in the chapter on 
constructive technique, being illustrated in Fig. 599. 

In shifting the occlusion from distal to normal in some cases in 
which the permanent teeth are nearly all erupted, it will be found that 
although the molars may respond readily to the intermaxillary force, 
the cuspids and bicuspids, especially in the upper arch, may not be so 
easily moved in the desired directions through the application of the 
elastics from the hooks upon the upper expansion arch to the distal 
ends of tubes on lower molar clamp bands. In these cases, Dr. F. M. 
Casto has suggested the use of intermaxillary elastics between individual 
banded teeth of the upper and lower arch to overcome the difficulty, as 
in Fig. 491, and their use in this manner has been attended with very 
gratifying success. 

Excessive Overbite. — A feature of no small importance in many 
cases of distal occlusion is the excessive overbite in the incisor region, 
which, if not overcome, will militate against the success of the treatment 
through the abnormal action of the inclined cusp planes of the incisors. 

Often, the lower incisors will be completely hidden from view by 
the upper incisors, in some cases striking the gums lingual to the upper 
incisors and causing absorption of the soft tissues. Again, it will be 
observed that the lower incisors occlude with the gingival ridges of 
the upper incisors, enhancing their protrusion, and initiating an 
inflammatory condition of the peridental membranes of the upper 
incisors. 

A rational method of treatment consists in the wearing of an appli- 
ance which will depress the incisors in their sockets through the open- 
ing of the bite by means of an inclined plane in the incisor region, 
which at the same time allows of natural elongation of the molars 
and bicuspids. 
41 



04- 



ORTHODONTIA. 




The bite plate with inclined plane and with flat metallic hooks 
extending over edges of upper incisors, illustrated in Fig. 492, is of 
value in these cases in which the upper and lower incisors need such 
depression in their sockets. This plate may be worn either before or 
after the application of the expansion arches. 

An esthetic modification of this principle has been embodied by 
Dr. Norman Reoch in an inclined plane of 26 gauge clasp metal, sol- 
dered to the lingual surface of 
gold bands, cemented upon the 
upper central incisors, Fig. 493. 
Dr. Reoch also reports the shift- 
ing of the occlusion from distal 
to normal in two cases with this 
appliance, and its use for the 
retention of simple cases of 
distal occlusion after treatment. 
Treatment of Class II; 
General Considerations. — In- 
asmuch as mouth-breathing is 

Fig. 492. . 

so commonly co-existent with 

distal occlusion, its diagnosis in any case should be followed by an 

examination of the nasal and pharyngeal passages by a competent 

rhinologist, and removal of respiratory obstruction if found. 

Tongue and lip habits should be noted and their effects counter- 
acted as soon as possible. 

Technique of Operative Treatment.— The operative treatment 
of Class II may be divided into two parts, the restoration of 
normal size and shape of the dental arches, and the shifting of the 
occlusal relations from distal to normal mesio-distal relations. 

The restoration of the size and shape of the 
dental arches is secured by the application of the 
expansion arches as in Class I, and the shifting 
of the occlusion by the use of intermaxillary force 
and anchorage. 

Treatment — Class II, Div. 1. — One of the 
most difficult cases of the first division of Class II which has 
come under the care of the author was that of a seventeen year 
old boy, the casts of whose teeth before treatment are illustrated in 
Figs. 494, 495, 496 and 497. 

As will be observed, the occlusion of the lower arch was completely 
distal to normal, the upper arch narrow with protruding incisors, 




Fig. 493. 



TREATMENT — CLASS II. 



643 



and the lower incisors retruding and cutting into the gum tissue behind 
the upper incisors. 

Mouth-breathing and abnormal lip function had assisted in pervert- 
ing occlusal relations to such an extent that the possibility of their 
normal relationship seemed highly improbable. The expansion 
arches were adjusted as indicated in the treatment of this division of 
Class II, except that the upper molar clamp bands were placed upon 




Fig. 494. 



the second molars so as to accomplish their distal movement before that 
of the upper first molars, thereby conserving anchorage in the use 
of the intermaxillary force. 

The lower first molars were used as anchorage for the lower ex- 
pansion arch to which a sufficient number of the incisors, cuspids 
and bicuspids, were ligated to ensure the stability of the entire lower 
arch as anchorage in opposition to the distal movement of the upper 
.second molars. After the upper second and first molars in succession 



644 



ORTHODONTIA. 



had been moved distally as far as it was deemed possible and practical, 
the upper second bicuspids were fitted with clamp bands and the 
intermaxillary force exerted upon them through the expansion arch 
resting in the tubes upon their buccal surfaces, the nuts in front 
of these tubes being kept tightened and the intermaxillary force 
being assisted in the distal movement of the bicuspids, as also in 
the previous movement of the first and second molars, by ligating the 




Fig. 495- 



upper incisors, cuspids and first bicuspids to the arch and turning up the 
nuts in front of the anchor tubes, thus pitting the anterior teeth en 
phalanx against the two teeth, either molars or bicuspids, which were 
being moved distally. 

About this time, the greater part of the resistance in the distal 
movement of the upper teeth having been overcome, the necessity for 
the use of the entire lower arch as anchorage ceased, and operation 
for the labial movement of the lower incisors was begun by tightening 



TREATMENT — CLASS II. 



645 



up the nuts in front of the tubes on the clamp bands upon the lower 
first molars, and this treatment was continued until the normal size 
of the lower arch was obtained. 

A change in the adaptation of the lower expansion arch was then 
effected in order to depress the lower incisors and elevate the bicus- 
pids, the expansion arch being sprung under hooks soldered to bands 




Fig. 496. 



upon these bicuspids, and over spurs soldered high up on the labial 
surfaces of incisor bands. 

This change in the occlusal plane of the lower arch was effected 
in due time, and, in the interim, the upper first bicuspids and cuspids 
were successively fitted with clamp bands and moved distally, the 
expansion arch being shortened to fit the successively smaller arcs, 
and the incisors being allowed to share in the distal movement after 
they were no longer needed to re-enforce the anchorage. 

Finally, it being found that the crowns of the lower incisors were 
inclining too much labially, their roots not moving forward enough 



4 



ORTHODONTIA. 



through ligating to a single arch, a partial second arch was hard 
soldered to the lower expansion arch, being dropped down by right 
angle segments until it was opposite to and about one-eighth of an inch 
labial to the necks of the lower incisors at the gingival line, and to this 
partial secondary arch the lower incisors were ligated, and through this 
leverage established, the incisal edges being firm against the primary 




Fig. 497- 



expansion arch, the apices of the roots of the lower incisors were 
gradually moved forward. 

This completed the actual treatment of the case except for the 
adjustment of retaining appliances which consisted of the usual spur 
and plane upon the upper and lower first molars, as in Fig. 584, and a 
lingual arch retention for the upper incisors, as well as a special appa- 
ratus for retaining the lower incisor roots in their labial positions. 
The latter consisted of bands upon the two lower cuspids, connected by 
a lingual wire running across the lingual surfaces of the incisors below 



TREATMENT — CLASS II. 



647 



the linguo-gingival ridge, and also connected by a labial wire'extending 
across the labial surfaces of the crowns of the incisors near the incisal 
edges. 





Fig. 498. 



Fig. 499. 




Fig. 500. 




The perfect restoration of occlusion in this case may be noted in 
the after-treatment models in Figs. 495 and 497. 

The remarkable improvement in the facial contour illustrated in 
Figs. 498, 499, 500 and 501, attest the value of perseverance and 



648 ORTHODONTIA. 

persistence in the following out of a preconceived method of treat- 
ment, which, although similar for the majority of cases of this class, is 
of necessity somewhat varied according to the peculiar requirements of 
the individual case. 

The treatment of this case covered a period of eight months' con- 
tinuous wearing of the appliances, during which time the patient 
did not once complain of discomfort, attending school while in session, 
and during a stay of one month in the country gained several pounds 
in weight, the intermaxillary elastics being worn in the interval. 

All retaining appliances were removed at the end of a year and 
a half, and a year after their removal, the occlusion was all that could 
be desired, having not shifted at all in its mesio-distal relations, and 




Fig. 502. 

the subsequent development of the alveolar process around the roots 
of the lower incisors had effected a most desirable change in this region. 

A very typical case of Class II, Div. 1, is illustrated in Figs. 502 
and 503, the before-treatment models on the left exhibiting full distal 
occlusion of the lower arch, the protrusion of the central incisors in the 
upper arch, accompanied by all the displeasing and inharmonious facial 
lines of the mouth-breather as seen in the short upper lip, and the 
rolling of the lower lip under the upper incisors, illustrated in the front 
and profile pictures of the case before treatment in Fig. 504. 

The expansion arches were adjusted to both upper and lower dental 
arches in a manner similar to the adjustment described in the case 
just preceding, except that considerable lateral spring was given to 
the upper expansion arch to obtain the effect of widening the upper 
arch posteriorly and retruding the upper incisors. 



TREATMENT — CLASS II. 



649 



The treatment of the case was aggravated by the loss of the lower 
right first permanent molar, as it was necessary to regain this lost 
space by banding the second bicuspid and ligating it to the lower 
expansion arch by a spur soldered a little in advance of this tooth, and 
turning up the nut on the expansion arch until normal occlusal re- 
lations were established, the intermaxillary force on this side being 
made strong enough by doubling the elastics to resist too great a distal 
movement of the second molar. 

The models on the right of Figs. 502 and 503 illustrate the very per- 
fect occlusal relations which were established, and the pictures on the 
right of Fig. 504 exhibit the improvement in the profile as the result of 
treatment. 




Fig. 503. 

The retention in this case consisted of interlocking spurs extend- 
ing from upper to lower molar clamp bands, the upper arch being also 
retained in its altered shape by a lingual arch connected with the upper 
molar clamp bands, and attached to incisor and cuspid bands. 

Early Treatment of Class II. — The advantages of undertaking 
the treatment of Class II cases at an early age, about the time the 
first molars are erupted into occlusion, if not before, cannot be over- 
estimated. 

Much of the success of cases of this class treated at this early 
age is due to .the careful oversight of the orthodontist during the 
shedding of the deciduous teeth and the eruption of their permanent 
successors. 

A case of Class II, Div. 1, in which treatment was begun at nine 



0=;o 



ORTHODONTIA. 



years of age, is illustrated in Fig. 505. The first permanent molars 
and the four incisors in each arch were the only permanent teeth 
erupted as indicated by the model at the top of the cut. In the treat - 




Fig. 504. 



ment of this case, besides the expansion and change of shape of the 
arches individually, the first permanent molars were immediately 
shifted in their occlusal relations until the correct relation of the arches 



TREATMENT- 



XASS II. 



651 



was established, as noted in the model on the left, making it possible 
for the normal eruption into occlusion of the remaining unerupted per- 
manent teeth, which were very carefully watched during the retention 
period until their normal locking into occlusion was assured, and the 
final result, shown in the model on the right of the cut, obtained. 

Of no small importance in the treatment of the cases of this class 
in which most of the deciduous teeth are still present is the develop- 
ment of the dental arches individually to a size which will be in better 





^^^B B B 


B ■ B „ mt '"" <j3^B 

^B B 'M^iS^m^ -in 



Fig. 505. 



proportion to the arch of the permanent teeth as it should be when all 
of the permanent teeth are erupted. For example, in Fig. 506, the 
uppermost cast represents an upper arch of a case of bilateral distal 
occlusion in a child seven years old. Its uniform shape and size 
give no clue to the proper amount of development this arch should 
receive other than a slight anterior expansion for the accommodation 
of the lateral incisors. The treatment of this upper arch was carried 
out to the extent shown in the cast on the left of the cut while the occlu- 
sion was being shifted, and even at this stage, there was no indication 



65a 



ORTHODONTIA. 



of the extent of development of this arch for the permanent benefit 
of the entire denture. At this time, the Hawley diagrams were called 
into use, that for .37 incisor being applied first to the cast before 
treatment, where it was seen that posterior expansion of the arch was 
indicated. Its reapplication to the second cast (on the left of the cut) 
revealed the fact that posterior expansion was indicated here, also, and 
lateral spring was used in the expansion arches until the measurement 
of the line of occlusion of the upper cast coincided with the pre-deter- 




Fig. 506. 

mined arch line of the diagram as seen in the cast on the right of 
Fig. 506. 

The criticism might be made here that it would hardly seem advis- 
able to enlarge an undeveloped dental arch in a seven year old child 
to a size which would correspond to that of an adult, but the results 
of added experience with this manner of development seem to bear out 
its advisability, especially when it is considered that there is some re- 
action during retention, and in those cases in which the arch is not over- 
expanded, as it were, appliances often have to be reapplied and added 



TREATMENT — CLASS II. 



653 



expansion obtained for the accommodation of permanent teeth which 
still seem to be retarded in eruption for lack of space. 

In the author's opinion, this is the ideal method of treating these 
cases, the lower dental arch being developed to correspond with the 
upper, and both retained during the period when the deciduous molars 
and cuspids are sufficiently firm to offer substantial resistance in 
retention, which would be during that period immediately following 
the eruption of the first permanent molars, and between the usual ages 




Fig. 507. 



of six and eight years. During the period of shedding of the deciduous 
molars and cuspids, it is almost impossible to obtain proper lateral 
expansion of the dental arches, since the first permanent molars would 
be the only teeth at this time which could be laterally moved. 

Class II, Div. 1, Infra-occlusion.— One of the most difficult 
complications occurring in any class of malocclusion is that of the open 
bite, or lack of occlusion extending from the central incisors distally 
sometimes as far as the first and second molars, the arches being 
separated anteriorly from one-sixteenth to one-half an inch, according 
to the degree of malformation present. 



654 



ORTHODONTIA. 



The inability to close the teeth anteriorly renders mouth-breathing 
more or less of a necessity, since lip function is almost entirely lacking 
in these cases, and the distortion of the features is much more dis- 
pleasing than if only the distal occlusion were present. 

The combination of open bite malocclusion and distal occlusion 
is such as to increase the difficulties of treatment, and sometimes 
to baffle the efforts of the most expert operator. 

In the treatment of an open bite distal occlusion of the first divi- 




sion of Class II, the advisability of applying force for the restoration 
of the normal mesio-distal relationship simultaneously with or pre- 
vious to the application of force for the closing of the bite, will depend 
largely upon the age of the patient and the extent of the separation of 
the anterior teeth. 

In a child under twelve years of age, the greater possibilities of 
development and growth of the alveolar process and underlying bony 
tissues of maxilla and mandible, might call for much more ideal treat- 
ment than in a more mature person. 

For example, the distal occlusion and open bite malocclusion would 



TREATMENT — CLASS II. 



655 



respond readily to treatment, and if normal breathing and lip function 
were restored and an effectual retention of the restored occlusion be 
secured in the child under twelve, success in the attainment of ideal 
results may be somewhat assured. 

In the adult the conditions for ideal treatment are very unfavor- 
able, since, although it might be possible to restore the normal rela- 
tions of occlusion and close the bite by the efficient use of intermax- 
illary force, the indefinitely continued use of the same force, with 




Fig. 509. 



a multiplicity of bands and wires for the retention of the normal rela- 
tionship, would render it somewhat unfeasible in the majority of cases. 

However, there is a method of treating such a case which appeals 
to the author as reasonable and practicable, both from his own ex- 
perience and from that of others, viz., to close the bite by grinding down 
the cusps of molars and bicuspids, allowing the front teeth to occlude. 

To illustrate, in Figs. 507 and 509, is represented an open bite bilat- 
eral distal occlusion of a fifteen year old boy, an habitual mouth- 
breather, anemic in temperament, and with so few of the teeth in contact 
that mastication of his food was an impossibility. To add to the 



6^6 



ORTHODONTIA. 



difficulties of treatment, the upper right first and second molars were 
in lingual occlusion, and the lower left first molar was decayed away 
to the roots. 

In order to be conservative of anchorage, the first step in the treat- 
ment was to bring the upper molars into buccal positions, and allow 
them to settle into occlusal relations with the lower molars before 
proceeding with the further treatment of the case. 

The expansion arches and rubber elastics were then adjusted as in 




Fig. sio. 



Fig. 490, for shifting the occlusion, which was successfully accomplished 
after a few months' treatment, but with the result that the anterior open 
bite was somewhat increased, as is usual in these cases. 

Although not assured of successful retention of the mesio-distal 
relationship of the arches and the occlusion of the anterior teeth, 
intermaxillary force was applied between the upper and lower incisors, 
cuspids, and bicuspids, as in Fig. 511, with the result that although 
these teeth moved more or less readily into occlusion, the appearance 
was not as much improved as might be expected, the incisors elongating 
to an abnormal extent, and not carrying the process with them. 



TREATMENT — CLASS II. 



657 



The intermaxillary force was withdrawn, and the anterior teeth 
allowed to settle back into their former positions, and the method of 
treatment changed in a manner that has proved of more permanent 
value. 

The author conceived the idea of so grinding the molar cusps of 
both upper and lower molars to close the bite that the inclined planes 
could be made to act as a permanent retention for the restored mesio- 
distal relationship of the arches, and by very carefully grinding one 
cusp at a time, and exaggerating the distal inclines of the lower and 
the mesial inclines of the upper molar cusps, this desirable result was 
effected, having retained the normal mesio-distal relationship now 
for over six months without the aid of any appliance such as the inter- 
locking planes usually used for the purpose. 




Fig. 511. 

The front view of the restored occlusion may be seen in Fig. 508, 
and the effectual interlocking of inclined planes of the cusps of the 
molars and bicuspids in Fig. 510 is of more than passing interest in view 
of the difficulties surrounding this class of cases in which distal occlu- 
sion, open bite malocclusion, and the confirmed habit of mouth- 
breathing were such insurmountable obstacles to any other method of 
treatment. 

One very gratifying feature of the treatment was that the boy had 
been examined by a rhinologist previous to coming under the author's 
care, and, although adenoids had been found, it was considered best to 
await the results of orthodontic treatment before they should be re- 
moved, and upon referring the case back to the nose and throat spe- 
cialist, he was unable to find any adenoids, which was a surprise, as 
such an occurrence had not before been recorded. 
42 



O58 ORTHODONTIA. 

The disappearance of these adenoids was no doubt due to the ex- 
pansion of the upper arch, and restoration of normal occlusion, which 
gave better opportunities for normal breathing and better masticating 
function, so that the tonsillar growths were reabsorbed through a 
restoration of functions which meant increased metabolism and con- 
sequent improved nutrition. 

The author has performed the operation of grinding the cusps of the 
molars and bicuspids in open bite malocclusions of the other two 
classes with very gratifying success, taking care that the inclined planes 
be preserved in the grinding, and be made to serve the purposes of 
articulation as well as occlusion by trying the articular movements of 
the mandible during the process, and seeing that the stress of articular 
mastication was properly supported by both buccal and lingual cusps 
of molars and bicuspids, as is done in the grinding of artificial teeth 
upon an articulator constructed upon the Bonwill principle. 

In very severe cases of open bite malocclusion, it may be found 
necessary to devitalize the pulp of one or more of the molar teeth, since 
the pulp cavity will have to be partially encroached upon in order 
to do sufficient grinding to secure occlusion of the anterior teeth, 
and yet this need not be considered an objection in view of the benefits 
obtained through the proper performance of masticatory function, 
and the correction of the mouth-breathing habit. 

Treatment of Class II, Div. 1, Subdiv.— The characteristics of 
the subdivision of Div. 1, Class II, are very similar in the general 
appearance of the dental arches to those of the full first division, the 
upper incisors being protruded, the upper arch narrow, and the facial 
disfigurement almost identical, the distinguishing feature of the sub- 
division being the unilateral distal occlusion, one lateral half exhibiting 
normal mesio-distal relations. 

The treatment, therefore, follows along the same lines as if the 
occlusion was distal bilaterally, except that it is unnecessary to shift 
the occlusion on the normal side, although the intermaxillary elastics 
may be applied on that side to assist in balancing the forces on each side 
of the rrouth. 

Figs. 512 and 514 exhibit a case of Class II, Div. 1, subdivision, in 
which the right lateral half is in distal occlusion, the left being in normal 
mesio-distal relations in the region of the first permanent molars. The 
space for the eruption of the lower left second bicuspid being partially 
lost, through premature loss of the deciduous second molar, the lower 
left first bicuspid and cuspid drifted into this space until they occupied 
distal positions. 



TREATMENT CLASS II. 



6 59 




Fig. 5r2. 




Fig. 513. 



66o 



ORTHODONTIA. 




Fig. 514. 




Fig. 515. 



TREATMENT — CLASS II. 



66 1 



The expansion arches were applied in the same manner as de- 
scribed for the treatment of the full bilateral distal occlusion, the mesial 
force upon the lower left first molar being compensated by the distal 
force exerted by the expansion arch in forcing the lower left cuspid and 
first bicuspid mesially into their normal positions. 

This latter movement was expedited by ligating from a lingual 
spur upon a band on the first bicuspid to a spur on the expansion arch 
slightly forward of the first bicuspid. 

After restoring the size and shape of the individual arches, and 




Fig. 516. 

shifting the occlusion to normal relations, the result shown in Figs. 513, 
and 515, in right and left occlusion was obtained. 

Intermaxillary retention was used in this case for a few months 
only, as the tendency of the dental arches was to remain in normal 
relations after normal occlusion and function of the occlusal planes had 
been restored. 

Treatment, Class II, Div. 2. — The occlusal characteristics of the 
second division of Class II include a distal occlusion of both lateral 
halves of the dental arches, with contraction of the anterior portion of 
the upper arch, usually presenting with some of the upper incisors in- 
clining lingually, or overlapping, as illustrated in the classification chart. 



00 J 



ORTHODONTIA. 



As with the first division of this class, the profile shows the effect 
of the distal occlusion, though not to such a marked degree, the lower 
third of the face being more uniformly receded from the normal pose. 

Although cases of this division are usually normal breathers, it is 
not unusual to find mouth-breathers among them. 

The distal occlusion in this division is probably in existence in the 
deciduous arches before the eruption of the first permanent molars, 
and the upper incisors are forced into lingual and overlapping positions 
through nature's effort to conform the arches to some uniformity in 




Fig. 517. 



size for better occlusion, the pressure of the lips being powerful factors 
in such arch conformation. 

Fig. 516 illustrates the right occlusion of a case of bilateral distal 
occlusion in an eleven year old child, the upper central incisors inclin- 
ing lingually and overlapped by the lateral incisors. In the treatment 
of this case, the intermaxillary elastics were applied for shifting the oc- 
clusion to normal mesio-distal relations, keeping the upper central 
incisors clear of the lower incisors by expanding the upper arch and 
moving the deflected central incisors towards their normal positions a 
little in advance of the mesial movement of the lower dental arch. 



TREATMENT — CLASS II. 



663 




Fig. 518. 




Fig 519. 



66 4 



ORTHODONTIA. 




Fig. 520. 




Fig. 521. 



TREATMENT — CLASS II. 



66 5 



The restoration of normal relations of occlusion in Fig. 517 is of 
exceptional interest in that the mesio-distal relations of the arches were 
not artificially retained, the normal function of occlusal planes of the 
teeth being sufficient to hold the dental arches in their normal pose. 

The only retaining appliance worn consisted of a lingual retainer 
for the upper central incisors, being attached to bands upon the lateral 
incisors. 

Treatment of Class II, Div. 2, Subdivision. — The occlusal rela- 
tions of one lateral half of the dental arches being normal in the sub- 




Fig. 522. 



division of the second division of Class II, treatment for shifting the 
occlusion is necessary only upon the lateral half which exhibits distal 
occlusion. 

Expansion of both arches, however, may be necessary, especially 
the upper arch. 

A characteristic case of this subdivision is illustrated, before and 
after treatment, in Figs. 518 and 519, right occlusion, and 520 and 
521, left occlusion. 

The distal occlusion is on the right lateral half, and the apparent 
simulation of a distal occlusion on the left side is due to the closing up 



000 



ORTHODONTIA. 



of the space for the lower second bicuspid which is unerupted, allow- 
ing the first bicuspid to drift back until it is in contact with the first 
molar, carrying along with it by lack of anterior development, the cus- 
pid and incisors on the left side. 

An X-ray of the left side of the mandible revealed the presence of 
the second bicuspid in its proper place but, of course, unerupted. 

Upon the adjustment of the expansion arches, the upper with hooks 
for the intermaxillary elastics, and the lower with a spur opposite the 
lower first bicuspid which was banded and ligated to the spur, the 
intermaxillary elastics were applied to both sides of the arches, that 
on the right being adjusted to shift the distal occlusion to normal, 





Fig. 523. 



Fig. 524. 



and the one on the left to reenforce the lower molar anchorage which 
is to resist the force used to move the cuspid and bicuspid on that side 
forward in the line of the arch. 

The treatment consumed nine months time, but in no other case 
has the author seen such apparent inclination of the teeth to move- 
ment into normal positions, and the arches to assume normal sizes and 
forms under the manipulation of the appliances as described. 

Immediately upon the removal of the appliances, the case presented 
the appearance seen in Fig. 522, in which the anterior part of both arches 
seems to be abnormally protruded, a condition which it has been er 
roneously claimed the orthodontists of the "new school" are apt to ob- 
tain as a result of their treatment without extraction. 



TREATMENT OF CLASS III. 667 

From four to six weeks after this model was made, the teeth had 
settled back through the guidance of the retaining appliances to the 
beautiful relations of occlusion shown in Figs. 519 and 521. 

The before and after treatment profiles of this case, Figs. 523 and 
524, show a decided improvement in the art relations of the face. 

TREATMENT OF CLASS III. 

Etiology and Diagnosis of Class III. — This class presents with 
bilateral or unilateral mesial occlusion of the lower dental arch, and, 
in the extreme, is probably the most disfiguring of any class of mal- 
occlusion. 

The maxilla is usually considerably arrested in development, and 
the mandible protruded, with its incisors inclining lingually. 

Most all of the cases of Class III are mouth-breathers, and nasal 
obstructions are unusually persistent. 

Accompanying many of these cases is the condition of "open bite" 
malocclusion with its added difficulties of treatment. 

The inception of mesial occlusion is during a very early period in 
child life, when it is least noticeable in the facial lines, and yet it is at 
this early period when the malocclusion should be diagnosed and the 
abnormal overcome conditions which are causative of it, if the most 
beneficial results are to be obtained. 

In severe cases of this class, the angles formed by the rami and body 
of the mandible disappear, leaving almost a straight line from the chin 
to the ear. 

These cases may usually be diagnosed from the profile, the mandi- 
ble being protruded, and the upper lip receding, but they are simulated 
in appearance by the "apparent lower protrusions" of Class I. 

The etiological factors are somewhat obscure, although it is believed 
that the habit of holding the mandible forward to assist in breathing 
has a strong tendency to cause the mesial occlusion. 

The conditions of arrested development are usually persistent, the 
upper arch remaining small and undeveloped, and the lower arch 
changing in form according to the general direction of abnormal ten- 
sion of muscles. 

Technique of Operative Treatment. — The operative treatment of 
Class III may be divided into the restoration of the normal size and 
shape of the dental arches, and the shifting of the occlusion from mesial 
to normal relations. 

The use of the intermaxillary force for shifting the occlusion is 
necessary, as in Class II, although the direction of the force and the 



66S 



ORTHODONTIA. 



manipulation of the anchorage is exactly the reverse from that in the 
second class. 

The direction and points of application of the intermaxillary force 
in treatment of Class III may be seen in Fig. 525, the elastics extend- 
ing from the distal ends of the tubes on upper molar clamp bands, 
to the hooks on lower expansion arch. 

The arches are illustrated without ligatures, so that the inter- 
maxillary anchorage may be more clearly shown. In actual treat- 
ment, proper ligation of the teeth in both dental arches to the expansion 
arch should be made according to the tooth movements desired, and the 
degree of re-enforced anchorage necessary in either arch. 

It is also necessary, in extreme cases of this class, to shift the anchor 




Fig. 525. 



bands from first molars to bicuspids in the lower arch, in order to con- 
serve anchorage and secure distal movement of the bicuspids. 

Owing to the fact that mesial movement of the teeth requires 
less force than distal movement, appliances almost always operate 
to move the teeth of the upper arch mesially more than to move the 
teeth of the lower arch distally in these cases. 

It is considered especially advantageous in this class of cases when 
there is present a deep overbite, or the overlapping of the upper over the 
lower incisors after shifting of the occlusion, as the increased length 
of the inclined cusp planes serve to more effectually retain the restored 
relations of occlusion than where but a short overlapping is present. 

It is advisable to begin the treatment of this class of malocclusion 
as early as it is possible to manage the child, for with added years comes 
an exaggeration of the deformity, the mandible assuming a mere for- 
ward pose, and the shape of the bone and the relations of the muscles 



TREATMENT OF CLASS III. 



669 



becoming conformed to an abnormal condition which makes it much 
more difficult and sometimes impossible to completely overcome. 

Treatment of Special Cases. — Figs. 526 and 527 illustrate 




Fig. 526. 

models of the case of the seven year old boy, from whose throat the 
adenoids and tonsils shown in Fig. 380 were removed at the beginning 
of treatment. 




Fig. 



527- 



Small molar clamp bands were fitted to the diciduous second molars 
and the 17 gauge expansion arches adjusted as in Fig. 525, the inter- 
maxillary elastics being attached well forward upon hooks on the lower 
expansion arch. 



O70 ORTHODONTIA. 

The occlusion was changed in a few weeks to that shown in Fig. 527 
and a persistent retention by means of the buccal spurs was established, 
and the case dismissed to be seen only at intervals of a couple of months, 





Fig. 528. Fig. 529. 

until the permanent teeth should erupt, in order that any untoward 
developments might receive immediate attention, should they arise. 

The front and profile pictures are exhibited in Figs. 381 and 382 and 
5-28 and 529. 

After a year's retention, the development of the facial lines through 




Fig. 530. 

the establishment of normal functions of occlusion and respiration 
has been most gratifying. 

Another case of this class, the before treatment models of which are 
shown in Fig. 530, and which was treated by Dr. M. T. Watson, is unusu- 



TREATMENT OF CLASS III. 



671 



ally interesting in view of the fact that the restoration of occlusion and 
facial lines was accomplished solely by means of the Angle chin cap 
and headgear, a combination which has fallen somewhat into disuse 
since the general adoption of intermaxillary force for the mesio-distal 
changes in occlusion. 




Fig. 531. 

Beginning with a very gentle elastic pressure for the first few days 
of treatment, two Number 33 Goodyear elastic bands were adjusted 
between headgear and chin cap on each side, followed in the course 
of a week by the substitution of a Number oooj for the lower of the 




— . 



Fig. 532 



two bands, which represented the maximum of force used in the 
treatment. 

Aside from a slight crowding of the lower incisors, the results 
of about six weeks' treatment produced almost normal mesio-distal 
relations of the dental arches, the final occlusal relations established 



672 ORTHODONTIA. 

being shown in Fig. 531. The necessity for the subsequent use of appli- 
ances inside of the mouth for perfecting the occlusal relations does not 
detract from the scientific value of the method just described for early 
treatment of this class of cases, especially as it is the only recorded case 
in which the treatment was confined solely to the use of the chin re- 
tractor, and therefore exhibiting "a change which must necessarily be 
confined to the shape of the mandible itself, or to a change in the tem- 
poro-maxillary articulation, or both, the latter probably being the case." 
(Watson.) 

Fig. 532 illustrates the before and after treatment profiles of the 
case, the latter picture being taken about four months after the first 
one. The slight prominence of the lower lip in comparison with the 




Fig- 533- 

upper may be accounted for by the loss of the upper deciduous central 
incisors during the treatment, and the lack of the permanent centrals 
being sufficiently erupted to lend any contour to the upper lip. 

A comparatively simple case of this class is illustrated in Fig. 533 
before and after treatment (of the right side). This case was under- 
taken just as the bicuspids were erupting to occlusion and the change 
from mesial to normal occlusion as a result of treatment gave the cus- 
pids and bicuspids an opportunity to complete their eruption into nor- 
mal locking with the inclined planes of their antagonists. 

The expansion arches were placed upon both upper and lower arches 
and the intermaxillary elastics stretched from hooks soldered well 
forward upon the lower expansion arch to the distal end of the buccal 
tubes upon the upper molar clamp bands, as in Fig. 525. When the 
upper incisors are but slightly distal to the lower incisors as in this 
case, the first effort should be directed to moving the upper incisors 



TREATMENT OF CLASS III. 



673 



into positions mesial to the lower incisors, so as to gain the advantage 
of the inclined planes of the lingual surfaces of the upper incisors 
acting upon the labial inclined planes of the lower incisors during the 
rest of the treatment, for until this change is made, the reverse action 
of the inclined planes of the incisors will tend to prevent a change in 
occlusion of the molars. 

To accomplish this movement of the upper incisors, the lower ex- 
pansion arch was securely ligatured to the lower incisors and bicuspids, 
and the lower arch used as a stationary anchorage, as it were. The 
upper incisors were then ligated to the upper expansion arch, the nuts 
in front of the anchor tubes turned up tight twice a week and the inter- 





Fig. 534. 



Fig. 535- 



maxillary force being constantly in action, not only prevented the upper 
molars from distal movement, but hastened the mesial movement of 
the upper incisors. 

After this change in the occlusion of the incisors was effected, the 
intermaxillary force continuing in action, produced the change from 
mesial to normal occlusion of the lower molars. It will be observed 
from the cut that some expansion of both arches was accomplished at 
the same time. 

Even with such a slight change in occlusion as is exhibited in this 
case, a very decided improvement in the facial lines is seen in the com- 
parison of the before and after treatment profiles in Figs. 534 and 535. 

A much more difficult case than the one just described on account 
43 



674 



ORTHODONTIA. 



of increased age and consequent greater density of alveolar tissues and 
conformation of occlusion and facial lines to abnormal conditions 




Fig. 536. 




Fig. 537. 

is illustrated in Fig. 536, being the before and after treatment models 
observed from the left side. 

Orthodontists have been cautioned against the possibility of ab- 



TREATMENT OF CLASS III. 



675 



normal eruption of the lower third molars during .or after the period 
of distal movement of the lower second and first molars in cases of this 
class, and while it is advisable to observe unusual precautions to pre- 
vent any maleruption of these teeth, the experience of the author in 




Fig. 538. 

this case and other similar cases, leads him to believe that in the majority 
of cases the restoration of occlusion and consequent proper function of 
the maxillae, may aid rather than interfere with the normal develop- 
ment of the third molars. The lower third molars in this case erupted 




Fig. 539. 

into their normal positions soon after treatment was finished, and with 
no more difficulty than if the operation had not been performed. 

The change in the profile is apparent from a comparison of the 
before and after treatment pictures in Fig. 537. 

Treatment of Unusually Complicated Cases of Class III.— 



0;6 



ORTHODONTIA. 



There arc many cases occurring in practice which seem to be excep- 
ionally difficult to diagnose and treat on account of the loss of many 
of the permanent teeth, and the consequent complications caused by 
the migration and elongation of remaining teeth in already contracted 
arches. 




iTG. 540. 



A case of this character, age twenty years, belonging to Class III, is 
exhibited in Figs. 538 and 539, before and after treatment of both right 
and left sides of the mouth. The loss of many of the teeth by caries 
and necessary extraction, and the elongation of teeth which had no 




Fig. 541. 

antagonists, rendered it exceedingly difficult to treat, especially as the 
problems of anchorage for the use of intermaxillary force seemed 
rather uncertain. 

By a careful conservation of anchorage, however, the case was finally 
brought to a successful completion, the after treatment models being 



TREATMENT OF CLASS III. 



6 77 



shown on the right of Fig. 538 and 539, with retaining appliances in 
position. 

In this case the plate plays a very important part, not only in retain- 
ing temporarily the spaces regained for permanent teeth, but also supply- 
ing artificial substitutes for the missing natural teeth. 

A view of the upper casts of this case in Fig. 540 shows the retention 
of five of the anterior teeth with the lingual wire soldered to right 
cuspid and left lateral incisor bands, and a roof plate, with spring 
clasp attachments and three artificial teeth, effecting the retention of 
the rest of the teeth in the upper arch. 




Fig. 542. 



Another plate with spring clasp attachments and artificial substi- 
tutes for natural teeth, accomplishes the greater part of the retention 
of the lower arch as illustrated in Fig. 541. 

The profile of this case, before and after treatment, is exhibited in 
Fig. 542, the improvement in contour being very pleasing. 

At a later period, the plates were removed and bridge-work inserted 
for permanent retention and increased function of mastication which 
was attained. 

The author would not advise undertaking the treatment of cases of 
malocclusion, especially of the most severe and complicated cases in 
this class, without the operator be assured from his own experience of 
successful results. 

A case, for example, like that illustrated in Fig. 543, presents 
such difficulties in the way of treatment, that the operation of resection 



6;8 



ORTHODONTIA. 



of the mandible for the purpose of securing the best results in improved 
mastication and facial contour has not infrequently been recommended. 
The infrequency of the operation of mandible resection, and the 
reports of a few failures in the hands of incompetent surgeons, has not 
aided in making it more desirable. The operation has been success- 
fully accomplished by the general surgeon, and it is believed by the 
author that in the near future, it will be more commonly performed and 
by the trained oral surgeon, especially with the help of the orthodontist. 




Fig. 543- , 

In the particular case illustrated in Fig. 543, the author performed 
an orthopedic operation which resulted not only in improvement in 
masticatory occlusion, but in a transformation of the disfigured facial 
lines into those of a most pleasing character, besides restoring the func- 
tion of correct phonation in speaking. 

The operation consisted in opening up an artificial space upon each 
lateral half of the maxilla, between the cuspid and first bicuspid, the 
width of a bicuspid tooth, moving the six anterior teeth forward to 
occlusion with the lower incisors, by a conservative use of intermaxillary 
force and special manipulation of the expansion arches. 



TREATMENT OF CLASS III. 



679 



At the same time, the teeth in the lower arch were moved distally 
as far as distal inclination of the lower incisors, and the accompanying 
movements of the upper teeth would allow, until the result shown in 
Fig. 544 was attained. The upper arch was retained by a fixed lingual 
arch soldered to bands upon the cuspids and first bicuspids, with buc- 
cal hooks upon the bicuspid bands, and with elastics extending from 
these to hooks on lower cuspid bands for a continuation of the in- 
termaxillary force as retention. 




Fig. 544. 

Artificial teeth, soldered to the lingual retaining wire, artistically 
filled up the opened spaces until such time as permanent bridge-work 
could be substituted for the retention. 

The improvement in the profile may be seen upon comparison of 
the before and after treatment pictures in Figs. 545 and 546. 

Double Resection of the Mandible. — We are indebted to Dr. 
Max Ballin, of Detroit, Mich., for the first published illustrations of 
a successfully operated case of double resection of the mandible, the 
detailed description of which is given here in condensed form. 

The patient was a young man twenty-two years of age, who pre- 



6So 



ORTHODONTIA. 



sented himself to the surgeon on May 10, 1907, for possible surgical 
treatment of a protruded mandible, which orthodontic treatment had 
for some reason failed to remedy. 

The extent of the protrusion measured one-half inch from the labial 
surfaces of the upper incisors to the lingual surfaces of the lower incisors, 
and the relations of the two dental arches in occlusion was such that it 
was almost impossible to masticate the food. (See. Fig. 547.) 

The loss of several teeth from each lateral half of the mandible 
left spaces in which considerable resorption of the process had taken 





Fig. 545- 



Fig. 546. 



place, and from which it was thought advisable to cut comparatively 
uniform sections of the mandible, and readjust and unite the anterior 
and posterior sections. 

Previous to operating, Angle's fracture bands were fastened to the 
teeth on either side of the area from which the sections were to be 
cut, by Dr. Jackson, a dentist who was called in consultation. The 
operation was performed on May 20, 1907, at Harper Hospital, 
Detroit. Ether was administered, and the incision made in the soft 
tissues under the lower border of the body of the mandible. The soft 
tissues were separated from the buccal and lingual surfaces of the bone 
in the region to be resected, and the mucous membrane was detached 
from the alveolar process with a curved elevatory, care being taken not 
to make the slightest entrance into the oral cavity. 

A trapezoid shaped piece was then resected from the mandible 



TREATMENT OF CLASS III. 



68 1 



with a circular saw driven by an electric engine such as is used for tre- 
phining. In repeating the operation upon the other half of the man- 
dible, the old style chain saw was found to work much easier and took 
considerable less time. A Deschamps aneurysmal needle was used to 
lead the saw around the mandible. The base of the resected pieces 




Fig. 547. 



was about one-half inch in length and somewhat longer than the 
apices. 

Holes were drilled through the lower edges of the remaining seg- 
ments of the mandible, the segments were adjusted together, and silver 
wires were inserted from one segment to the other on each side. After 
suturing the external wound, the union of the segments was made more 



68a 



ORTHODONTIA. 



secure by the ligating of the buttons upon the fracture bands within 
the mouth, from the teeth on the anterior segment to those upon the 
posterior segments. 

The entire operation, with the exception of the ligation of the 
fracture bands, was performed outside of the mouth, so as to make it 
as aseptic as possible. 

The patient made a quick recovery, being in the hospital about 
one week, the wound healing by first intention. The after treatment 
model and profile in Figs. 548 and 549 show a marked improvement 
over former conditions. 

Dr. Ballin remarks: "In the first place, strict asepsis should be 





Fig. 548. 



Fig. 549- 



a condition without which successful work is impossible. Therefore, 
opening of the oral cavity during the operation should not occur as 
this would certainly lead to suppuration and non-union of the bones. 
If the teeth are extracted during the operation, communication between 
the external incision and the extraction wound will always take place. 
I would recommend, therefore, to extract the teeth necessary to be 
removed for the resection, first, and then wait some months until *the 
extraction wound is completely healed and atrophy of the alveolar proc- 
ess has taken place." 

In commenting upon this operation, the author believes that Dr. 
Ballin has solved the difficulties in the way of preventing the inception 
of septic conditions, in operating entirely external to the oral cavity. 



TREATMENT OF CLASS IV. 683 

One suggestion made by Dr. Angle in regard to preparation for this 
operation seems an improvement in the technique and that is the re- 
section of the previously made plaster cast of the mandible, and re- 
adjustment with the upper cast for the purpose of obtaining the best 
occlusion, and cutting out a section of the mandible which most nearly 
approximates the plaster section which was removed. In this way, 
the lines of direction for the chain saw might at least be approximated 
more perfectly than without any measurements, and the mandible 
better adjusted for occlusal relations. 

In any event, the co-operation of surgeon and orthodontist seems 
advisable in working out the details of double resection of the man- 
dible in order that the peculiar skill and experience of each may serve 
the purpose of obtaining the most beneficial and scientific results. 

TREATMENT OF CLASS IV. 

The characteristics in occlusion of Class IV being a mesial occlu- 
sion upon one lateral half, and a distal occlusion upon the other lateral 
half of the dental arches, as observed in the classification chart, the 
indications for treatment are a distal shifting of the occlusion in the 
former, and a mesial shifting of the occlusion in the latter. 



Fig. 550. 

These movements may be secured at the same time by operating 
upon each lateral half as if they were independent of the other in their 
mesio-distal relationship, making use of the intermaxillary force as 
indicated by the attachment of hooks and elastics in Fig. 550, the 
elastic extending from a hook upon the upper expansion arch upon one 
side to the distal end of the lower tube on the molar clamp band, and 
from a hook upon the lower expansion arch to the distal end of the 
buccal tube on the upper molar clamp band upon the other side. 



6S 4 



ORTHODONTIA. 



Dr. Norman G. Reoch has reported a case of this class in which the 
intermaxillary force applied in this manner brought the case to a suc- 
cessful completion. 

Restoration of the Lateral Half of the Mandible after Uni- 
lateral Resection. — Occasionally, one lateral half of the mandible is 
resected by the surgeon because of diseased conditions which render 
it necessary to cut away a sufficiently large area to make reoccurrence 




Fig. 551. 

of tumors, or further breaking down of adjacent healthy tissues im- 
possible. 

If the remaining half of the mandible is not controlled by mechan- 
ical means, the contraction of the cicatricial tissue will draw the for- 
ward portion of the remaining section of the mandible to one side, 
and the unequal stress of muscular pressure will tip it inward, a case 
of this kind being represented in Fig. 551, the operation of resection 
having been performed seven years before presentation of the case 
to the author for orthopedic treatment. 

The facial lines in this case were very much distorted, see Fig. 554, 



TREATMENT OF CLASS IV. 



68: 



the point of the chin being swung around or across the face from left 
to right, and the patient being unable to restore the mandible and chin 
to their median positions. 

Various methods have been used to swing the mandible back to 
position in the median line, chief among which may be mentioned the 
lower partial plate hinged to the upper molar teeth upon the same 
side as the resection. 




Fig. 552. 



The author prefers the use of intermaxillary force, because of its 
power and directness, and quick accomplishment of results. 

In this case, the intermaxillary elastics were applied as in Fig. 553, 
from a hook upon the right side of an expansion arch firmly ligated 
to the upper dental arch, securing as nearly as possible stationary 
anchorage, to another hook soldered to the mesial surface of a heavy 
gold band upon the lower central incisor, this band being reenforced 
by adjoining bands upon the lateral and cuspid, united with solder, 
and by one-half of an expansion arch extending from the lower first 
molar to the central incisor band, upon the surface of which it engaged 



686 



ORTHODONTIA. 




Fig. .553. 





Fig. 554. 



Fig. 555- 



THE PROBLEM OF EXTRACTION. 687 

at right angles with a short vertical tube. The intervening teeth 
were ligated to this partial arch for further reenforcement. 

As it was necessary to stretch the cicatricial tissue to some extent, 
it being composed of considerable fibrous elastic tissue, the size and 
number of the elastic used were varied until the resistance of this 
tissue was overcome, and the half of the mandible returned gradually 
to its proper median register, being at the same time tipped outwardly 
until the occlusal plane of the teeth was correct. 

A removable vulcanite substitute with artificial teeth was made 
for the resected half of the mandible, the upper arch was expanded 
and formed into proper shape, and the resulting occluding position 
of the arches is seen in Fig. 552. 

Fig. 555 illustrates the great improvement in the face consequent 
upon this operation. 

These, and similar operations, are as much within the field of the 
orthodontist, as if the entire mandible were involved, and it is fitting 
that those who are unfortunate enough to possess these oral dis- 
figurations should receive the benefit of the training of the experienced 
orthodontist. 

THE PROBLEM OF EXTRACTION. 

Extraction of the teeth of either deciduous or permanent set in 
orthodontia, must be viewed from a different standpoint than in 
general dental practice, since the whole aim of the orthodontist is 
the restoration of the dental arches in occlusion with the full comple- 
ment of teeth, while the dentist is intent upon the restoration of contour, 
etc., of the individual tooth. 

If the general practitioner could see his work through the light 
of occlusion, articulation and development, all of his cases for bridge- 
work would be sent to the orthodontist for restoration of normal 
sized arches, and the regaining of spaces partially or completely, 
from which teeth have been extracted. 

The radical departure from the older methods of treatment by the 
"new school" of orthodontia in the adoption of conservative methods 
of treatment, bases its assurance of propriety upon the premises that 
in the attainment of the normal and ideal in occlusion, all of the 
dental organs must be preserved in the correction of malocclusion. 

This arbitrary standard is not made by the specialist, but it is 
indicated by the perfection of the occlusion in the normal and ideal, 
in which is recognized the value of the individual tooth as a factor 
in the preservation of the integrity and regularity of the arches of teeth, 



688 



ORTHODONTIA. 



the loss of one or more teeth from either arch causing deformity to 
just the degree of extraction to which it is resorted. 

With this conception of treatment in orthodontia, extraction as a 
beneficial procedure, that is, towards restoring the normal in occlu- 
sion, is of course absurd, for with extraction comes mutilation of the 
arches, impairment of speech and mastication, and the formation of 
lines of inharmony in the face which are surely not desirable as a 
result of the efforts of the orthodontist. 

A very large per cent of the deformed arches of teeth which present 
to the specialist, are caused by the premature extraction of deciduous 
teeth, or the unwise extraction of permanent teeth. 

A very frequent question asked of the specialist by a parent is as 
to the advisability of extraction of one or more of the deciduous teeth 




Fig. 556. 



in the mouths of their children to "make room" for the permanent 
teeth. The acquiescence by the dentist in the unwisdom of this falla- 
cious and pernicious idea has led to the wholesale extraction of decidu- 
ous teeth in the vain hope that the space thus created will allow the 
permanent teeth more room to erupt. 

The result of such operations is just exactly the reverse of that 
which is intended, for the dental arch instead of being any larger, 
becomes still more contracted through the contraction of the space of 
the lost deciduous teeth, and the permanent teeth have less room 
to erupt than if none of the deciduous teeth had been extracted. 

Results of Extraction of Deciduous Laterals. — For example, in 
the cast on the left of Fig. 556, the deciduous lateral incisors were re- 
moved in the belief that the two permanent centrals would have more 



THE PROBLEM OF EXTRACTION. 

room for eruption, as they were apparently crowding somewhat in 
their effort to erupt. As a result of this treatment, the centrals 
erupted almost perfectly in alignment, but it will be noticed that their 
distal angles are almost in approximation with the deciduous cuspids, 
and that there is no space left for the eruption of the permanent lateral 
incisors, necessitating an operation for the restoration of these spaces 
and anterior development of the arch as seen in the cast on the right 
of Fig. 556, the deciduous laterals immediately erupting upon being 
released from imprisonment. 

Results of Extraction of Deciduous Cuspids. — A Class I case, 
in which the lower deciduous cuspids have been prematurely ex- 
tracted, with the complete loss of their space and anterior arrest of 
development in consequence, is illustrated in Fig. 557. 




Fig. 557. 

The lower incisors, having lost their support in the cuspid region, 
have become inclined lingually, and the upper incisors have been 
forced back against the lower incisors through the pressure of the 
lips and abnormal function. 

The treatment of this case was undertaken at the time it presented 
with this condition of occlusion, and both arches were expanded, 
in the lower, the cuspid spaces being regained, as shown in the casts 
at the top of Fig. 558, and in the upper, the centrals moved forward, 
and the space for the right first deciduous molar regained, as shown 
in the casts in the lower part of Fig. 558 and this relationship estab- 
lished through proper retention until the eruption of the permanent 
cuspids and bicuspids. 

A very noticeable improvement in the profile through this treat- 
ment may be seen in the central portion of Fig. 558, showing that the 
44 



(X)O 



ORTHODONTIA. 




Fig. qd 



THE PROBLEM OF EXTRACTION. 69 1 

harmony of the facial lines is effected by such apparently slight arrest 
of development as is caused by the loss of the lower deciduous cuspids 
and an upper deciduous molar. 

Result of Extraction of Deciduous Molars. — The model on 
the left in Fig. 559 exhibits a case in which the lower deciduous molar 
was prematurely extracted, the subsequent closing up of its space, and 
arrested anterior development of the lower arch, with the dropping 
lingually of the upper incisors in an attempt on the part of nature to 
obtain a contact occlusion with the lower incisors. The model on the 
right illustrates the case after the space has been regained for the 
extracted molar, the arches harmonized anteriorly in occlusion, and a 
band and bar retention attached from cuspid to first molar in the 
lower arch, pending the eruption of the permanent bicuspids. 




Fig. 559. 

The loss by extraction of any of the deciduous teeth has a similar 
destructive effect upon the occlusion, the difference being only in 
degree. 

In Fig. 384 is illustrated a case in which all of the deciduous teeth 
were extracted before the age of nine years, and the arrest of develop- 
ment of the arches is very plainly seen, although it is comparatively 
uniform throughout both arches. 

Evil Effects of Extraction of Permanent Teeth.— In the loss 
of teeth by extraction from the second dentition, somewhat similar 
effects upon the dental arches are observed as those produced by 
extraction or premature loss of the deciduous teeth. 

Successively, the results of extraction of one or more of the perman- 
ent teeth are the destruction of the integrity of the dental arches, the 
destruction of occlusion and articulation, and finally the marring of 
the facial lines. 



(H)J ORTHODONTIA. 

The extent of the deformity is usually proportionate to the degree 
of the extraction, every additional tooth lost causing just that much 
more aggravation of conditions and change to the abnormal. 

Relative value of First Permanent Molars. — In view of the 
prevalency of the extraction of the first molars it may be well to con- 
sider first their relative value and then the result of their extraction from 
the arch. 

Some of the more important reasons for their preservation in the 
arch are as follows: 

i. They are the first of the permanent molar teeth to erupt, 
and during the period of shedding of the temporary dentition, afford 
the broadest and best masticating surfaces in the mouth. 

2. By reason of their great size and strength, they are the only 




Fig. 560. 

teeth that can serve as a means of preserving the normal relationship 
between the dental arches, and consequently the symmetry of the 
face, at a time when no other of the permanent teeth, except the in- 
cisors, are erupted to occlusion. 

3. Their presence is an aid in the forward development of the 
mandible. 

4. Statistics comparing the relative frequency of caries in the 
first and second molars prove the second molar more often carious 
than the first. 

5. The first molar, on the average, is a better constructed tooth 
than either the second or the third molar. 

6. Its extraction is the cause of a large percentage of cases of 
malocclusion, and consequent facial inharmony. 

Results of Extraction of First Permanent Molar. The historv 



THE PROBLEM OF EXTRACTION. 693 

of the case of malocclusion in Fig. 560, dates its inception to the time 
of the extraction of the lower right first permanent molar, and the series 
of intricate changes in occlusion to the abnormal are commonly ob- 
served. 

The model on the right of the cut represents the left side of the 
case in occlusion, exhibiting normal cusp relationship of upper and 
lower teeth as far forward as the cuspid. 

The model on the left illustrates the destruction of occlusion and 
the shortening of the right lateral half of the dental arch as a result 
of the extraction of the first molar. 

To the student of occlusion, the changes in occlusal relations after 
the loss of the first permanent molar are more or less familiar, and 
it is comparatively, easy to follow the consecutive stages whereby 




Fig. 561. 

the ruination of otherwise beautiful dental arches has been accom- 
plished. 

Consequent upon the loss of the first molar in this case, ensued 
not only the tipping mesially of the second molar, but also the drift- 
ing distally of the second bicuspid into the space, followed by the 
distal movement of the first bicuspid, the cuspid and incisors, and 
the contraction of the whole arch. 

The effect of this contraction upon the upper arch is noticeable 
in the lingual positions of the incisors, and the torsion of the right 
lateral incisor. 

The closing together of the teeth in occlusion tends to force the 
lower right second molar still farther mesially, and to draw the right 
lateral half of the lower arch distally to a considerable extent. 

The occlusal views of the upper and lower arches in this case, in 
Fig. 561, illustrate, from this aspect, the mutilated arches, both being 



694 ORTHODONTIA. 

contracted and the upper arch flattened in the incisor region, produc- 
ing this effect in the facial profile, as a consequence. 

The author has observed a patient with a similar case of maloc- 
clusion, who was on the verge of nervous collapse as a result of such 
changes in occlusion as to make mastication painful and almost im- 
possible. 

A variation from these changes in occlusion as a result of the 
extraction of a lower second bicuspid is observed in Fig. 562. 

Although not revealed by the picture, the second bicuspid on the 
right side of the lower arch was also extracted so that the change in 
occlusion was comparatively uniform bilaterally. 




Fig. 562. 

Result of Extraction of Second Bicuspids. — The loss of these 
teeth has caused an apparent protrusion of the upper arch in Fig. 
562 as a result of the perversion of function of the occlusal planes and 
also of the lips, the lower lip tending to roll up under the upper in- 
cisors and force them still farther outward. 

The first and second molars in occlusion have retained the normal 
mesio-distal relationship of the arches, and the contraction of the 
lower arch has been entirely anterior to the first molars, the second 
bicuspid spaces being almost entirely closed. 

Complications in Treatment after Extraction of Teeth. — 
The treatment of cases of malocclusion caused, or mutilated, by ex- 
traction of the permanent teeth, is necessarily much more complicated 
than if the full complement of teeth were present, so that complete 
arch restorations as well as occlusal relations might be established. 

As a rule, it is imperative that all spaces of teeth which have been 



THE PROBLEM OF EXTRACTION. 



695 



lost through extraction should be restored and artificial substitutes 
inserted in order to secure harmony in occlusion between the dental 
arches. 

In the cast on the left of Fig. 563, it will be noticed that the lower 




Fig. 563. 

right lateral incisor is missing, it having been extracted for the pur- 
pose of "regulating" on account of its having been located in lingual 
occlusion. 

In the restoration of this arch to normal size, the space for the 
right lateral was regained, as shown in the cast on the right of Fig. 




Fig. 564. 



563. How much more scientific it would have been to have enlarged 
this arch to this extent when the case first presented with the lateral 
in lingual occlusion and to have restored it to its normal position in 
the arch. Here, indeed, is the clue to the proper solution of the case 



ooo 



ORTHODONTIA. 



and illustrates, in a nutshell, the impropriety of extraction either "to 
make room" or correct alignment. 

The before and after treatment models of the case viewed from the 
front in Fig. 564 illustrate the necessity of regaining the space for the 
lateral incisor and providing an artificial substitute in order to restore 
the normal relations of occlusion. 

If the upper arch only had been restored to its normal size and 




Fig. 565. 



shape, it would have been larger than the lower by the width of the 
missing lower lateral incisor. 

The illustration of a few practical cases in pairs, of the same class, 
one of the pairs having been treated by extracting, the other by restor- 
ation of normal occlusion, may serve, by comparison, to show the 
relative value of the two methods of treatment. 

Fig. 565 exhibits a Class I case in which the dentist, who originally 
had it in charge, thought it necessary to extract the upper first bicus- 



THE PROBLEM OF EXTRACTION. 



697 



pid on the left side in order to "make room" for the eruption of the 
left upper cuspid which was formerly in a position similar to that of 
the right cuspid seen in labial occlusion in the model on the left of 
the cut. 

The operation of extraction was performed as indicated, the upper 
left cuspid erupting into the space, partially, but so incompletely 
filling it that the patient was unwilling to have the same thing done 
upon the right side of the arch. 

On examination of the occlusal view of the upper and lower casts 
in the same cut, it will be observed that the lower arch is contracted 
anteriorly, the cuspids being in torso-occlusion, and if an operation 




Fig. 566. 



for expansion of both arches had been performed, normal occlusion 
could have been obtained. 

Fig. 566 illustrates a precisely similar case, both as to etiology and 
diagnosis, except that the malocculsion is limited to the left lateral half 
of the arches. 

The prognosis in cases of this kind is always favorable to treat- 
ment without extraction, and the diagnosis assures such splendid 
results as are shown in the after treatment model on the right of 
Fig. 566, the arches being restored to normal size and shape, and 
normal occlusal relations being established. 

Fig. 567 exhibits a somewhat more severe case than the one just 
described, but it might have been governed by the same laws in its 
treatment if they had been understood. 

Two mistakes were made in the treatment of this case, however; 



6qS 



ORTHODONTIA. 



one by the extraction of the upper second bicuspid, the other the 
neglect of the slight irregularity in the lower in the treatment of the 
case. The after treatment on the right shows alignment to a certain 




Fig. 567. 

degree but it will be noticed that the arch is still crowded, and that 
the possibility of harmonizing the arches and restoring occlusion is 
forever lost. All that was needed was the regaining of some lost space 
in the lower arch and the harmonizing of the upper arch to it, saving 
all of the teeth. 




Fig. 568. 

Fig. 568 illustrates a similar case in which the ideal has been attained 
in the restoration of normal occlusion without extraction, each occlusal 
plane having been moved into its correct relationship with its antag- 



THE PROBLEM OF EXTRACTION. 



699 



onist of the opposite arch, and the production of a harmonious 
result which is truly beautiful. These results were obtained some 
ten years ago when the principles of occlusion were much less known 
than now. 

Coming now to another class of deformities in which extraction 
of one or more of the bicuspids has been advised as of value in the 
reductions of protrusions such as is here illustrated, Fig. 569, let us 
note in the case the results of such extraction upon the arch. The first 
bicuspid was extracted and the anterior teeth drawn distally until 
the space of the extracted tooth was closed, a very common operation 
extant among the profession for the correction of this deformity. The 




Fig. 569. 



model of the completed case on the right exhibits no such harmony of 
contour as the models of the completed cases which are illustrated 
under the treatment of the first division of Class II. The curves are 
not graceful, the mutual support of the full complement of teeth has 
been lost, and a lame and crippled appearance is distinctly noticeable. 
N In the majority of cases in orthodontia, extraction of the teeth 
is not indicated, in fact, an almost iron clad rule has been established 
by some specialists operating from the basis of occlusion, condemning 
extraction in all cases. 

While this rule is a safe one to follow in the majority of cases, to 
attempt to practice it in every case would be entirely unwise, as there 
are cases in which it is not only impossible to restore normal occlu- 



700 ORTHODONTIA. 

sion, but in which extraction is indicated in order to obtain any sort of 
harmony of the occlusion. 

These exceptions do not necessarily lower the standard of perfec- 
tion which the restoration of the normal or ideal in every case might 
imply, since their very existence and the difficulty of their diagno- 
sis should, by the nature of things, compel the operator to use his 
best judgment and follow a safe rule. 

In what cases, then, is extraction advisable ? The answer to this 
question is the knotty part of the problem, for although we are cer- 
tain of the advisability of the procedure in some cases, to lay down a 
set rule for such cases would militate against the best results which 
might be obtained without extraction, for in two identically similar 
cases, extraction may be found necessary in one, while in the other, 
the restoration of the ideal in occlusal harmony may be easily 
diagnosed and obtained. 

Exceptions to the general rule of occlusal restoration in which 
it is advisable to extract does not give license to extract promiscuously, 
and the only hesitation which the author feels in attempting to point 
out these exceptions lies in the possible exaggeration of the number 
of cases in which the novice, because of his lack of experience, and the 
charlatan, because of his indifference, might feel justified in extracting 
teeth unnecessarily because of any loophole which the knowledge of an 
exception to the general rule of non-extraction might give them. 

But, the obligation laid upon the author, in the publication of a 
scientific work on orthodontia, which, to be scientific and most helpful 
to the general practitioner, should not be misleading, is so great, 
that to attempt to encourage the attainment of impossible results 
through non-extraction and futile attempts at occlusal restoration, 
would defeat the object of the promulgation of the truth which should be 
paramount in the building up of any science which tends in any way to 
benefit the human race. 

It might be correctly stated that extraction is advisable in some 
few cases in which it is impossible to obtain a satisfactory result 
after an intelligent and persistent effort in following out the laws of 
occlusal restoration. 

Or, in cases of monstrosities of tooth dentition, such as in extreme 
hypertrophy of the alveolar processes, where restoration of normal 
occlusal relations would only exaggerate the deformity and increase 
the inharmony of facial contour. 

So seldom is extraction indicated that in the author's practice, 
it has been resorted to in but four cases in ten years, and a similar 



RETENTION. 701 

record will be found in the practices of other specialists operating 
from a conservative basis. 

In cases already mutilated by extraction, in which it is not advisable 
to restore normal occlusion by regaining all spaces lost by such extrac- 
tion, it may be necessary to extract according to the requirements 
which are peculiar to the individual case, and for which no set rule may 
be established. 

In these cases, the advice of a specialist of at least five years' ex- 
perience in orthodontia ought to be sought, in order that an error 
in judgment may not be made through simple lack of experience. 

VIII. RETENTION. 

The Scope of Retention. — A clear perception of the field of re- 
tention necessitates a proper understanding of the ultimate purpose of 
the treatment of arrested developmental conditions in the dental arches, 
which is the restoration of function, through the stimulation of struc- 
tural development in the maxillary arches, and the attainment of 
the normal in occlusion and articulation. 

It will be inferred from this statement that the development and 
restoration of the normal in shape and size of the individual dental 
arch is the primary, and the attainment of normal positions of inclined 
planes of antagonizing cusps of occluding teeth the secondary, con- 
sideration in treatment, these two phases being so related, however, 
that the consideration of the one without the other would be incom- 
prehensive of the scope of orthodontia. 

Necessity for Retention. — In all treatment in orthodontia, the 
resistive qualities of the osseous structures in which the teeth are 
implanted, and of the fibrous elastic membranes with which they are 
surrounded, are mechanical as well as physiological factors which are 
present until long after treatment is completed, and unless these 
reactive forces are inhibited for varying periods after the completion 
of treatment, more or less of a return of former conditions of imper- 
fection of form, growth, and occlusal relations of the dental arches is 
inevitable. 

Added to these untoward influences the possible abnormal habits of 
mouth-breathing, thumb- and lip-sucking, and the abnormal tension of 
the muscles of the tongue, lips and cheeks, and the abnormal influence 
of inclined cusp planes, present in many cases, the forces which tend 
to resist normal development and function may be considerable. 

Retention may be defined as the maintenance of such development 
of the dental arches and relations of occlusion as may have been established 



702 ORTHODONTIA. 

through treatment, by a proper antagonism of any forces which may in- 
terfere with these normal structural and functional conditions. 

The establishment of mechanical resistance to these return tend- 
encies through appliances attached to the teeth must be sufficient so 
that an equilibrium between the forces of reaction and the applied 
resistance is obtained. An insufficiency of resistance in a retaining 
appliance would result in a partial return of former conditions. 

Retention, then, as in anchorage, is a measure of resistance values, 
the proper appreciation of which is essential to the permanence of 
results obtained in treatment. 

Retention Classified. — Retention may be classified as follows: 
Occlusal, simple reciprocal, intermaxillary, and occipital, according to 
the quality of resistance used in opposing the return forces. 

Of especial importance is the influence of the inclined planes of 
the cusps in retention, their normal function ending in occlusion and 
articulation, to preserve the integrity of the arches. 

Occlusal retention is the maintenance of the normal occlusal posi- 
tions of the teeth, individually or collectively, through the normal functional 
influence of the inclined planes of the cusps, and the contributory forces 
gained through restoration of arch integrity. 

In order to secure the harmonious working of the inclined planes 
it is necessary that not only should the full complement of teeth be 
present, perserving individual arch integrity by proximate contact, 
but that the normal size and shape of the arches be restored, which 
would include the restoration of articulating planes and compensating 
curves, etc. Experience will prove that articulating planes can be only 
approximately obtained in the correction of malocclusion, so compli- 
cated is the mechanism of articulation, and the lack of development 
of the arches in malocclusion so disturbing the harmonious working 
of the laws of articulation that accurate arch and cusp protection 
in articular movements is outside the range of possibility of treatment, 
except in special cases. 

In malocclusion there is abnormal function of occlusal inclined 
planes of cusps, often of respiratory mechanism, and tongue or lip in- 
sufficiency, and abnormal muscular pressure, which if not corrected 
will still continue their abnormal influence upon the arches of teeth. 

The nearer the approach to normal occlusion and articulation in 
the treatment of any case of malocclusion, the less need will there be 
for mechanical retention beyond that afforded by the normal action 
and reaction of the inclined planes of the cusps. 

It must be remembered however, that the restoration of the 






RETENTION. 703 

normal functions of occlusion and articulation does not counteract 
the tendency of the fibers of the peridental membrane and the alveolar 
process to assume their former relations of abnormality, except to 
to a slight degree, otherwise there would be very little need for mechan- 
ical retention of teeth and arches. 

The normal relations of occlusal inclined planes in the attainment 
of normal occlusion, cannot be depended upon alone, for retention, until 
after varying periods of fixed retention of the teeth and arches with 
mechanical appliances, except in simple and special cases. 

An upper incisor tooth, moved from lingual to normal occlusion, 
if there is sufficient overbite, will be retained by the action of the lingual 
incline of the upper incisor upon the labial incline of the lower incisor. 

The same effect will be observed where there is sufficient overbite 
in any of the upper teeth which have been moved into their line of 
occlusion from lingual occlusion and restored to the normal action 
of the inclined planes. 

To a lesser degree, also, the restoration of upper bicuspids and 
molars in buccal occlusion, lower incisors and cuspids in labial occlusion, 
and lower bicuspids in lingual or buccal occlusion, will be retained by 
the restoration of the normal influence of their inclined planes in occlu- 
sion. 

Infra-occlusion of the teeth demands long and persistent retention 
of corrected occlusion. 

Teeth which have been rotated, unless at a very early age, as during 
their eruption, will always need retention by mechanical appliances 
for varying periods of time. 

Anterior and posterior expansion of arches will also usually need 
retention for periods of time varying according to the degree or extent 
of the expansion, the age of the patient, the peculiarities of the case, 
etc. 

Extensive cases of Classes II and III, will always demand a very 
persistent mechanical retention, often for several years. 

Simple cases of Class II, especially of the second division, and its 
subdivision, and of Class III, are often retained by normal cusp in- 
fluence alone, as far as the mesio-distal relations of occlusion are 
concerned. 

Figs. 516 and 517 is an example of bilateral distal occlusion, Class 
II, Div. 2, which was retained in its mesio-distal relations entirely by 
the interdigitation of the cusps "of bicuspids and molars, although the 
upper incisors were retained by bands and spurs for a short time. 

Usually the retention of a corrected malocclusion is a matter of 



704 ORTHODONTIA. 

more than a few weeks in point of time, many cases requiring months, 
and some of the more severe, several years of fixation in order to 
overcome the resistance of the fibers of the peridental membrane, and 
the tendency of the arches to contract or assume their original forms 
and relationships after having been restored to a normal condition 
of occlusion, or after being mechanically developed up to a physiolog- 
ical limit. 

The retention of the deciduous teeth is a process of temporary 
fixation for the development of the arch alone, while the retention 
of the permanent teeth is often a necessity for their maintenance in 
their relative positions in the arch, although developmental changes 
are still going on. 

The length of time of retention of the arches of deciduous teeth, 
at the most, can only last until the eruption of the permanent teeth, 
in whole or in part. 

Permanent teeth, which have been moved into their normal lines of 
occlusion during eruption or immediately after, need retention for 
a far shorter time than if they have been confirmed in their abnor- 
mal positions for some time before being corrected. 

It is a well known fact in orthopedic and orthodontic practice that 
the rapidity oj the restorative or building up process in bony tissues, as 
after setting of fractures, is proportionate to the degree of fixation of the 
parts during the period immediately following the corrective operations. 

To the end, therefore, of shortening the time of retention, as well 
as obtaining a more perfect development and greater strength of the 
tissues surrounding the moved teeth, and avoiding the possibility of 
any loss from contraction of arches after expansion or regaining of 
spaces, the fixed retaining appliance, with cemented bands, is gener- 
ally to be preferred to any other. 

Simple retention is the antagonism of the forces of reaction by the 
support of the resistance of one or more teeth in the same arch which have 
not been moved, or which afford a comparatively stable resistance in 
opposition to these forces. 

For example, in Fig. 570, A, the central incisor which was in lingual 
occlusion is retained in position by cementing upon it a band with 
labial spur extending over the labial surface of each adjoining tooth, 
as shown at B in the same figure. The adjoining teeth may have 
shared in a general expansive movement to a slight degree, but would 
still afford a comparatively stable resistance for retaining the lingual 
tendency of the central incisor which was in lingual occlusion. 

A torso-mesial occlusion of the one central may be retained 



RETENTION. 705 

by the cemented band and lingual spur over the lingual surface of the 
other central which may, or may not have been moved to a slight ex- 
tent labially or lingually. An absolutely stable resistance in single 
tooth movements is, of course, to be preferred for retention purposes. 

Reciprocal retention is the counterbalancing oj the return tendencies 
of two or more teeth in the same arch or in opposite arches by the antag- 
onism or opposition oj their reactive forces. 

Simple reciprocal retention would be represented by the antagon- 
ism of the reactive tendencies of two teeth which have been moved in 
opposite directions, as illustrated in Fig. 571 the two centrals being 

A B 





Fig. 570. 

rotated in opposite directions, and the retention consisting of two bands 
soldered together, and cemented upon the centrals. 

Compound reciprocal retention would be represented by the antag- 
onism of the tendencies to return of several teeth in the same or opposite 
opposite arches. 

Intermaxillary retention may be compound reciprocal retention 
between teeth of opposite arches 

In the retention of the expanded arch, as in Fig. 575, the resistance 
of one lateral half is pitted against that of the other, and is an illustra- 
tion of compound reciprocal retention. 



Fig. 571. 

Another example of simple reciprocal retention is illustrated in 
Fig. 572, the lateral incisor and first bicuspid being reciprocally an- 
tagonized in their return tendencies by the band and spur method. , 

Intermaxillary retention consists of the continuation of the use of 
intermaxillary force in cases of mesial or distal shifting of occlusion in 
such a manner that a reciprocation of force and resistance is established 
which is capable of the retention of the mesio-distal changes in 
occlusion. 

In persistent cases of Class II or III, the necessity for the use 
of the intermaxillary force for a considerable time after treatment, 
45 



;oo 



ORTHODONTIA. 



in order to retain the mesio-distal relations of the dental arches, is 
evident to the experienced orthodontist. 

This form of retention is illustrated in Fig. 585, in a case of the 
first division of Class II. 

Occipital retention consists of a continuation of the wearing of 
the headgear and traction bar for counteracting the resistance offered by 
the incisors to being heid in lingual positions. 

In general, the field covered by retention may be divided as follows: 
Corrected malocclusions of individual teeth, expanded or contracted 
arches, and mesial or distal changes in occlusion. 

To a certain extent, then, the retention of any given case is indi- 
cated as much bv its classification as is the treatment, and it is evident 




Fig. 572. 



that a favorable prognosis can not be made without a foreknowledge 
of the possibilities of a successful retention. 

Retention of the Expanded Arch. — The age at which treatment 
is begun, and the number of permanent teeth erupted, will necessarily 
require a variation of forms of retention according to the demands of 
the individual case. 

If uniform development of the dental arch has occurred during 
treatment, that is, the arch being expanded in the molar as well as the 
incisor region, the retention will have to be so applied that this ex- 
pansion will be uniformly retained. 

It has been customary in a large percentage of cases of expanded 
arches to retain the anterior portion of the arches by a fixed appliance, 
and to pay little attention to the molar region, many times allowing 
the molars to settle back into the same arch form as before treatment. 



RETENTION. 



707 



While this may be done in some cases with impunity because of 
the lack of necessity of much expansion in the molar region, the 
author is convinced that in the large majority of cases, not only does 
the dental arch need expansion in the molar reigon, but a fixed reten- 
tion as well. 

The Deciduous Arch.— The earliest indications for retention in 
the deciduous arch are after a certain amount of expansion of the 
anterior portion of this arch for securing development enough for 
the eruption of the incisors and cuspids, and possibly the bicuspids. 

The need for a fixed retention of a part or of the entire deciduous 
arch, during a varying period of natural development and including 




Fig. 573. 

the eruption of the permanent teeth provided for in the retention, is 
apparent. 

Retention of Anterior Part of Developing Arch. — An appliance 
which will effectually retain the anterior part of the arch during the 
developing period and attached entirely to the deciduous teeth, is 
shown in Fig. 573, being the retention of the anterior portion of the 
expanded arch shown in Fig. 446, chapter on operative technique. 

The deciduous cuspids are banded and connected by a lingual wire 
of 18 or 19 gauge, B &S., and short spurs are extended distally from 
the lingual surface of the cuspid bands upon the lingual surface of the 
deciduous molars. A great amount of strength in a retaining appliance 
attached to the deciduous teeth is never necessary because of the slight 
resistance they offer to the action of force appliances in their movement, 
due to their small short roots, and the cartilaginous nature of the al- 
veolar process. 




708 ORTHODONTIA. 

If more development of the anterior portion of the arch is re- 
quired after the expansion has been carried on as far as possible, the 
retainer may be constructed as in Fig. 574, in which the lingual wire 
slips into short tubes soldered to the cuspid bands, and by pinching 
with the wire stretching pliers, as suggested by Dr. Angle, the arch 
may be still further expanded in this region during the period of reten- 
tion. The lingual wire in this case should be constructed of platinized 
gold sufficiently soft to be easily stretched in this mariner without 
breaking. 

Retention of the Entire Deciduous Arch. — In case that the 
deciduous arch has been uniformly developed by expanding anteriorly 

and posteriorly, an immediate need exists 
for the retention of all the increased 
width and length of the arch which has 
been gained in the treatment. 

To illustrate, the upper arch in Fig. 
447, although the permanent central in- 
cisors and first molars are present, is 

still the same in width as the deciduous 
tig. 574. 

arch, and in development is still a de- 
ciduous arch. The central incisors being .39 inch wide, require, 
according to the Hawley measurements, an arch considerably larger 
than the average. 

Having been expanded during a period when the deciduous teeth 
present were comparatively firm in their attachments, the crowns 
of the permanent teeth being moved laterally through their envelop- 
ment by the roots of the deciduous molars, the indicated retention 
in the case is a fixed retention of the entire deciduous arch until such 
time as the natural developmental processes have been completed 
so that the eruption of the remaining permanent teeth may take place 
in a sufficiently enlarged arch. 

According to these indications, the retention exhibited in Fig. 575 
was adjusted, bands of irido-plantium being fitted to the deciduous 
cuspids and second molars, and connected by a lingual retaining wire 
of 19 gauge, B. & S., iridio-platinum, soldered to their lingual sur- 
faces, and extending across the lingual surfaces of the first permanent 
molars. 

In order to secure a more accurate fit, the lingual wire was adjusted 
and soldered to the bands upon the plaster cast, the bands having been 
removed with the impression. The central incisors were retained with 
two iridio-platinum bands united with solder, and cemented in position. 



RETENTION. 



709 



A slight lateral spring may be given to the lingual retaining wire to 
assist in further stimulus to lateral development of the arch if necessary. 
Retention after Anterior Expansion. — Where the arch has been 
expanded anteriorly, it is an essential that the increased width of the 
arch should be retained for some time, so as to allow the development 
of the alveolar process and the overcoming of the forces of reaction. 
For example, if the arch has been expanded anteriorly to allow the 
centrals or laterals to be rotated, etc., the retention of these individual 
teeth in their lines of occlusion is not sufficient in most cases, as the 




Fig. 575. 



reactive force in the contractive tendency of the arch will soon cause a 
malocclusion to appear, such as the overlapping or torsion of one or 
more of the incisors. 

It is advisable, therefore, to always retain the positions of the six 
anterior teeth by means of a fixed retaining appliance which will 
hold the width gained between the cuspids, such as is shown in Fig. 576, 
adding a lingual spur to the first bicuspids when they have also been 
included in the lateral expansion. 

Fig. 577 illustrates the expansion and retention of the anterior por- 
tion of an upper arch, in which space was made for the eruption of 



;io 



ORTHODONTIA. 



the cuspids. Bands were cemented upon both of the first bicuspids 
having previously been united with the strong 16 gauge bar of platinized 
gold extending along the lingual surfaces of the incisors, and having 
spurs of 21 gauge gold wire bent around the distal angles of the lat- 
eral incisors to the liabial surfaces to hold the four incisors intact. 

This appliance is as simple and 
esthetic as can possibly be constructed 
for a case of this character, and it 
might well be used as a standard re- 
tention for similar cases in which no 
rotation of any extent is necessary in 
the incisor region. 

The Lingual Arch Retainer. — 
The use of the lingual arch retainer, 
as suggested by Dr. Lourie, invites 
many possibilities of practical and 
esthetic retention of the dental arches, 
because of its efficiency and inconspicuousness. 

Consisting of an iridio-platinum wire closely adapted to the lin- 
gual surfaces of the incisors, cuspids and bicuspids, and attached at 
either end to the ends of the lingual screws of the molar or bicuspid 
clamp bands, see Fig. 578, it is correct in principle since it provides 




Fig. 576. 




Fig. 577. 



for complete retention of the entire dental arch after general expan- 
sion, at the same time providing for Such retention of the individual 
teeth as may be necessary. 

The retention of teeth which have been moved labially or lingually, 
extruded or intruded, may be accomplished with this method by at- 
taching hooks to the lingual surfaces of individual bands upon the 



RETENTION. 711 

teeth, and bending these hooks above or below the lingual arch, and in 
such positions as will tend to overcome the particular resistance re- 
quired. 

In Fig. 578 its use in retaining the extrusion of the incisors in a 
former case of openbite malocclusion is effective, especially with the 
spurs over the occlusal surfaces of the deciduous molars, enlisting their 
resistance in supporting the lingual arch in position which in this 
instance is attached to clamp bands upon the deciduous molars. 

In Fig. 584 the lingual arch presents a feature of additional value 




Fig. 578. 

in its prevention of the tipping or rotation of the teeth which sup- 
port the buccal spurs for retention of the mesio-distal relations of 
the arches. 

Anterior and Posterior Arch Retention. — A very ingenious and 
efficient retaining appliance, designed by Dr. Henry Baker, of Boston, 
for anterior and posterior retention is illustrated in Fig. 579. 

In effect, it is a lingual arch, KL, of clasp wire, 17 gauge B. & S., 
closely adapted to the lingual surfaces of the incisors, cuspids, and 
bicuspids, soldered anteriorly to the lingual surfaces of gold bands 
upon the cuspids, with its distal ends engaging in rings upon the lin- 
gual surfaces of gold bands upon the molar teeth. 

The labial wire, F, extending from one cuspid band to the other, is 



12 



ORTHODONTIA. 



designed to retain the incisors from a return to positions of torsal 
or other malocclusion. 

For greater accuracy of adaptation, this appliance is preferably 
made upon a cast, the four bands having been previously constructed 
upon the natural teeth, and an impression taken of the arch with them 
in position. 

The molar bands, M and N, are first cemented into place, and then, 




Fig. 579. 

after filling the cuspid bands with cement, the distal arms, K and L, are 
slipped into the lingual rings on the molar bands, and the anterior 
portion of the appliance forced into position upon the anterior teeth, 
there being enough play in the lingual molar rings for this downward 
movement of the appliance. 

Retention of Mesio-distal Changes in Occlusion. — As cases 
of the second and third classes of malocclusion present the greatest 




Fig. 580. 

difficulties in the way of treatment, so also do they require exceptionally 
difficult retention, for in addition to the necessity of retaining each 
dental arch in its corrected form and size, including the malposed 
teeth which have been restored to normal positions, it is almost always 
essential that the mesio-distal change in occlusion shall be persistently 
retained for some time after treatment, varying with the age of the 
patient and the extent of the mesio-distal malocclusion. 



RETENTION. 



713 



Occasionally a case presents in which the restoration of function 
of the occlusal inclined planes needs no other retention than the 
normal action and reaction of these inclined cusp planes upon each 
other in occlusion and articulation. A case of this kind belong- 




Fig. 581. 

ing to the second division of Class II is described under treatment 
of this class and illustrated in Figs. 516 and 517. 

As illustrative of the fact that mesio-distal retention upon the molars 
is not always necessary after treatment in the divisions of Class II, 
in early treated cases, Dr. Norman Reoch reports a case in which the 




Fig. 582. 

retention consisted simply of an inclined plane of gold attached to the 

upper central incisors, illustrated in Fig. 493, tending by its action at 

each closure of the mouth to cause normal locking of occlusal planes. 

Antagonizing Spurs. — The simplest retention of the normal 



7 14 ORTHODONTIA. 

mesio-distal relations of the dental arches after shifting the occlusion is 
by means of spurs soldered to the buccal surfaces of upper and lower 
molar clamp bands, which are so related that they act as an inclined 
plane continually forcing the occluding molars into their proper cusp 
relationship during each closure of the jaws. 

Fig. 580 illustrates the positions of the buccal spurs for the retention 
of the mesio-distal relations established after treatment of a case of 
Class II. 

In retention of the mesio-distal relations after treatment of Class 
III, the positions and angle of inclination of the buccal spurs should 
be reversed from that described for Class II. 

The buccal spurs upon the molar bands are constructed of square 
wire, preferably of platinized gold or iridio-platinum, giving flat 




Fig. 583. 

surfaces for the antagonizing of the two spurs in occlusion. These 
spurs are adjusted after a method suggested by Dr. M. T. Watson, 
being a modification of the spur and plane method used by Dr. Angle. 

Occasionally it will be found that the buccal spur on the upper 
molar clamp band in Class II may be dispensed with, allowing the 
lower buccal spur to antagonize the plane of the mesial angle of the 
mesio-buccal cusp of the upper first molar, especially in cases in which 
the permanent bicuspids are unerupted. 

The buccal spurs are also effectual in retaining single molar or 
bicuspid teeth which have been moved buccally or lingually into 
proper occlusion, as described by Dr. Angle. 

Figs. 581 and 582 illustrate the right and left occlusion of a case of 
Class II, Div. 1, before and after treatment. It is useless in cases 



RETENTION. 



715 



in which the upper incisors are protruded to the extent shown in this 
case to expect that restoration of function of the inclined planes of 
the incisors will be sufficient to retain the normal relations of occlusion 
which have been established in the incisor region, and it is advisable 
to retain the mesio-distal change in occlusion until the eruption of the 
permanent bicuspids in a case undertaken as early as this one. 

A buccal and occlusal view of the retaining appliances used in this 
case is shown in Figs. 583 and 584, the antagonizing spurs upon upper 
and lower molar bands serving to retain the normal mesio-distal rela- 
tionship established between the arches, and the lingual arch, acting in 




Fig. 584. 

conjunction with bands upon the incisors, attached with lingual hooks, 
effectually retains the upper arch in its normal form and the upper 
incisors in their normal positions. 

In severe cases of Classes II and III, it is always advisable to 
use intermaxillary retention in a continuation of intermaxillary force 
so gauged that it will not carry treatment farther, but simply balance 
the resistance in either arch. 

In Fig. 585, the application of this force for the retention of a case of 
the first division of Class II, a lingual bar extending across the incisors 
from one cuspid band to the other, and soldered to bands upon the 
central incisors, having a hook at the disto-labial angle of each cuspid 



7 i6 



ORTHODONTIA. 



band, the intermaxillary elastics extending from these hooks to similar 
hooks upon the buccal surface of clamp bands upon the lower first 
molars. 

The expansion of either arch may be retained at the same time by 
lingual arches of iridio-platinum, attached to the cuspid bands and 




Fig. 585. 

extending from the lingual screw of one clamp band to that of the other 
in the upper arch, and supported by such additional bands in the 
incisor region as may be necessary. The use of the lingual arch re- 
tainer in the lower dental arch is very similar to that in the upper, 
its attachments varying with the necessities of the case. 

IX. CONSTRUCTIVE TECHNIQUE. 

Advantages of Technique Instruction. — The author has long held 
the idea that a technique course in the construction of certain parts of 
orthodontia appliances is an essential training to the student in the 
mechanical treatment of malocclusion, and that the orthodontist of the 
future must be a constructive orthodontist. 

At almost every sitting of the patient, there is an opportunity to 
mechanically readjust some part of the appliance, to make a band 
for one tooth, with spurs for more direct application of the force, to 
provide for rotation in another, and such other changes or additions 
as suggest themselves to the mechanically trained operator as being of 
value in shortening the time or increasing the comfort of the operation. 

While it is unnecessary to construct the expansion arch and molar 
bands, and the traction screw, since they have been standardized and 
adaptable in the average case, it must be remembered that the angles of 
the tubes on molar clamp bands need to be frequently changed to suit 
the requirements of anchorage, and the breaking of such thin bands is 
not an uncommon occurrence, necessitating the repairing of the broken 
part if for no other reason than an economy of material. 



CONSTRUCTIVE TECHNIQUE. 717 

Assuming, however, that the simpler cases of malocclusion need 
little, if any, construction work, in addition to the standard appliance 
which only needs adjustment, the field of retention, with its unlimited 
possibilities in the mechanical construction of retention appliances 
requiring a combination of art and esthetics in the production of an 
efficient and inconspicuous apparatus, looms up before one with a de- 
mand for the most consummate skill in the art of construction. 

To the lover of the art of orthodontia, in the varied characteristics 
of mechanical construction in retention, where the ready-made ap- 
pliance is of little, if any use, the mechanical and esthetic features pre- 
sent such scope for skill and originality as is not found in the same de- 
gree in any other part of the work. 

Materials for Construction of Appliances. — The first considera- 
tion in a material for the construction of appliances to be used in the 
mouth should be the selection of a metal or alloy that will be the least 
affected by the fluids of the mouth, and which in turn will least affect 
the surfaces of the teeth with which it comes into contact. 

Any orthodontia appliances in the mouth interfere more or less 
with the natural cleansing action upon tooth surfaces of the saliva, and 
the tongue and cheeks in mastication, and an appliance should not 
only be simple in design and application, but should be constructed of 
materials which will give the greatest immunity from caries. 

Providing the quality of efficiency is not impaired by such a selec- 
tion of material, the choice of metal or alloy for appliance construction 
is of paramount importance, the manner of its application and subse- 
quent adjustment being of less moment. 

Choice of Metals for Appliances. — So many different metals 
have been advocated in the past for the construction of appliances that 
it is necessary to point out from the standpoint of clinical experience 
those metals or alloys which are of the greatest advantage for use in 
the mouth, where physiological conditions must be taken into account. 

German silver has occupied the field of orthodontia to the exclu- 
sion of almost every other metal or alloy for over fifteen years in the 
United States, and for mechanical efficiency in the possession of the 
requisite tempers for the manufacture of arches and bands, is almost 
an ideal material for the purpose. 

From a physiological standpoint, however, there is much to be de- 
sired in a combination of metals for appliances to be used in the mouth 
than is possessed by the alloy of German silver. 

A material which will not discolor nor corrode, and which is not 
attacked by the fluids of the mouth, at the same time possessing the 



718 ORTHODONTIA. 

requisite temper for all the parts of an appliance, is much to be pre- 
ferred. 

The alloys of gold and platinum possess all these requisite qual- 
ifications, and the author has succeeded in obtaining such perfection 
in these alloys that any degree of temper, from the hardness of 
iridioplatinum to the softness of pure gold or pure platinum, may 
be secured. 

German silver is acted upon by sulphuric, hydrochloric, and nitric 
acids ; even a weak acid like acetic acid will attack it, forming a com- 
bination of the basic acetates of copper, which at least is not desirable. 
Pyrozone and iodine attack it vigorously. 

In the mouth German silver discolors and in a large number of 
cases corrodes upon the surface, sometimes to the extent of perforating 
a molar clamp band. The pits formed by this corrosion become 
breeding places for bacteria, retaining, as they do, a certain amount of 
the soft foods in their cup-like pockets. 

Potassium sulfo-cyanate, which is normally present in the saliva, 
which gives immunity to caries when present in sufficient quantity, 
badly discolors German silver. 

German silver will sometimes leave a metallic stain upon tooth 
surfaces, which is difficult to remove, unless careful prophylactic 
measures are taken during the treatment of a case. 

The alloys of gold and platinum will neither corrode, discolor, nor 
be affected by any acid or alkalie, except aqua regia. 

The fusing point of platinum is 1775 Cent., of gold, 1075 Cent. 
An alloy composed of 90 per cent gold and 10 per cent platinum fuses 
at a temperature of 1130 Cent., which is very significant, proving that 
pure gold may be used as a solder upon this alloy without danger of 
fusing the latter, since the fusing point of the alloy is 55 degrees higher 
than the fusing point of gold. 

An alloy of gold, 84 per cent, and platinum, 8 per cent, with a small 
percentage of copper, forms an alloy that may be graded in temper by 
the variation in the percentage of copper to a degree of hardness not 
attainable by any workable alloy of German silver. 

Perhaps the most important feature of this alloy is that hard soldered 
attachments may be made to an expansion arch oj this combination without 
destroying the temper, a process which the German silver arch will not 
stand without having its temper taken out, and making it inefficient 
as an appliance. 

The point of chief importance in a gold alloy for appliance construc- 
tion is that it shall contain sufficient platinum so that the fusing point 



CONSTRUCTIVE TECHNIQUE. 719 

will be so high that the ordinary blowpipe flame will not melt it while 
soldering. 

Gold alloys without platinum can be used, but invariably when sol- 
dered attachments are made to the arch in these alloys, if anything 
higher than 18k solder is used, the gold alloy is in danger of being melted. 

With platinum alloyed with the gold in proper proportion, the author 
has soldered attachments to an arch of the alloy with 22k solder and 
even pure gold, an advantage that more than makes up for the slight 
difference in cost. 

The Molar Clamp Band. — This same alloy of gold, platinum, and 
copper, offers the most advantages for the construction of the parts 
of the molar clamp band, with perhaps the exception of the nut on the 
lingual screw, which does not need protection by having a high fusing 
point, and may be made of a gold alloy without the admixture of plati- 
num. 

Iridio-platinum is also very useful for the band part of the clamp 
band. 

Plain Bands. — Iridio-platinum in very thin sheet form, .005 inch, 
is an admirable material for the construction of plain bands, as it has 
every advantage of non-fusibility, lack of discoloration and corrosion in 
the mouth. 

Retaining Wires. — Iridio-platinum wire, in gauges from 20 to 16, 
B & S., may be used for retaining wires, varying in diameter according 
to the stress. On account of its extreme rigidity, smaller and more 
delicate wires may be used in iridio-platinum than in gold or German 
silver. 

Where extreme softness is desired in a retaining wire, platinum 
offers this quality in perfection, and when combined with gold, the 
temper may be varied to any degree to suit, at the same time retaining 
the high fusing point, which renders failure in soldering operations 
impossible. 

As far as expense is concerned, the author has found the use of the 
noble metals for appliances an investment, since their value as "scrap" 
alone is considerable at the end of a year. 

If the advantage of the "all gold" appliance is explained to the 
prospective patient, he is usually willing to pay the difference between 
its cost and that of the German silver appliance. 

In the author's estimation, the adoption of the "all gold" appliance 
has done more to raise the standard of orthodontia than any other re- 
cent advance in the science. 

The esthetic appearance of the appliances in the mouth gives the 



720 ORTHODONTIA. 

operator himself a better appreciation of his own work than if they were 
constructed of the base metals, and presented a discolored and unsightly 
appearance, and thus insures a greater interest in his work, which is 
the only stimulus towards advance in methods of treatment. 

The adoption of the "all gold" appliance is related to and is as 
imperative an advance in practice as sterilization of instruments, and 
prophylaxis, and the conformation of dental and orthodontic practice 
to their demands is only a question of time. 

Soldering Technique. — The attainment of skill in constructive 
technique in orthodontia lies chiefly in one's ability to perform dim- 
cult soldering operations in a rapid and efficient manner, involving a 
training of the eye as well as the hand in the approximate relationship 
of the aggregated units of a given appliance, without waste of time or 
effort. 

The workbench of the orthodontist is not complete without every 
facility for easier and more rapid methods of soldering than are obtain- 
able by the investment of pieces to be united, or the approximation of 
parts by the use of bulky tweezers , and the use of the large flame of the 
Bunsen burner. 

The requirements for this class of soldering operations are as follows : 

i. A blowpipe flame of proper fineness and easily controllable. 

2. Clean, bright surfaces on parts to be united. 

3. Easy flowing solders, cut to graded sizes for various purposes. 

4. A quickly acting flux in convenient form to apply. 

5. Perfect approximation and fixation of parts to be united. 
Taking up these requirements in order, the form of blowpipe should 

receive the first consideration. 

The necessities of the work require that a blowpipe should not be 
more than a few inches in height, the burner to be upon a substan- 
tial base, and having attached to it easily adjustable valves for both 
gas and air, the tip of the burner being so constructed that a continuous 
fine, needle point flame of sufficient intensity may be obtained, and 
varied in size and intensity by valve control to suit the needs of the vary- 
ing size and bulk of appliances to be soldered. 

The Kerr Blowpipe. — The most perfect blowpipe which answers 
these requirements, is the Kerr blowpipe, suggested by Dr. J. Lowe 
Young, and is illustrated in Fig. 586. 

While a compressed air outfit is most desirable in connection with 
a blowpipe of this kind, the ordinary bellows will answer the purpose, 
providing it is large enough, so that the foot does not have to be used 
in pumping except at long intervals. 




CONSTRUCTIVE TECHNIQUE. 72 1 

A clean, bright surface is always essential to a successful attach- 
ment of solder, and oxidized surfaces should be carefully polished with 
a fine sandpaper disk in the engine before soldering, or boiled in alum 
solution and polished on the lathe. 

The tendency to use too large pieces of solder may be overcome by 
grading the size of the pieces according to the size of the parts to be 
united, the larger parts requiring correspondingly 
larger pieces of solder than the smaller ones. 

The four sizes of pieces of German silver solder 
illustrated in Fig. 587, being respectively one- 
sixteenth of an inch square, one-sixteenth by one- 
eighth inch, one-eighth inch square, and one-eighth 
by three-sixteenths of an inch in size, will be found 
most convenient for all ordinary purposes. 

The smallest size may be used for soldering on 
spurs at right angles to bands, and the threaded fig. 586. 

portion of the anchor clamp band to the end of 
the band. The next larger size is adaptable for uniting spurs to 
bands parallel to the surface of the bands, the next larger pieces for 
uniting the short tubes of the anchor clamp elands to the bands, as 
well as in other places in which an equal bulk of solder is indicated, 
while the largest pieces of solder may be used in uniting the large buc- 
cal tubes of the anchor clamp bands to the bands, also useful in such 
unions as the buccal retaining spurs of heavy wire on the anchor clamp 
bands in Class II retention. 

It is possible in the use of German silver to perform a number of 
soldering operations in close proximity, using the same low fusing silver 

solder for each one without seriously endangering 

I — I LJ D the fixation of previously soldered parts, if the flame 

Fig. 587. is used fine enough and directed only upon that 

part of the appliance to be soldered last. 

The high fusing silver solder is a little contrary and the occasion 
for its use is seldom found. 

In the use of gold solder, on account of its thickness, the size of 
the cut pieces should not exceed the next to the smallest size shown 
in Fig. 588 for the maximum. 

The use of more than one grade of solder is especially valuable, 
for example, in constructing the plain band, which often requires 
a spur soldered so close to the line of union of the two ends of the band 
that in the second soldering operation for the spur attachment, the first 
union may easily become unsoldered where but one grade of solder is 
46 



I 22 



ORTHODONTIA. 



used for both. Again, in construction of retaining appliances, the 
advantage of the use of several grades of solder is apparent. 

Easy flowing solders of either gold or silver are obtainable at the 
depots, and in the use of the gold solders, for making attachments upon 
gold or platinum appliances, an intelligent use of the higher carats 
in the uniting of primary parts, with the consecutive use of a lower carat 
for secondary attachments, will give assurance of the success of each 
soldering operation in their order, and if the degree of heat is properly 
gauged, the union of a number of very small parts in close approxima- 



Fig. 588. 

tion may be much more safely accomplished than if but one grade of 
solder were used. 

Next in importance in soldering operations is the use of a flux which 
will quickly cleanse the oxidized surfaces so that the solder will flow 
readily. Borax is the usual constituent of all fluxes for hard solders 
of either gold or silver, and when properly calcined and prepared for 
convenient use, will answer every purpose. A favorite method of some 
operators is to have a specially prepared borax slate with various sizes 
of solder mixed with creamed borax on its surface, ready for immediate 
use. Considerable time is consumed in mixing the borax before every 
soldering operation in this manner, and the displacement of the sol- 




Fig. 589. 



der from position when placed in the flame is an annoying and not in- 
frequent occurrence. 

To alleviate these difficulties, the author has had prepared and 
placed upon the market a specially prepared wax soldering stick, of 
the size and shape shown in Fig. 588, and containing a calcined borax 
flux, which is not only instantaneous in application, but by means of 
the wax body, fixes the piece of solder in position so that it cannot be 
displaced before it fuses. The only caution necessary in its use is that 
the surface to be soldered should be slightly warmed, and not heated to 
redness, before touching with the wax stick. 



CONSTRUCTIVE TECHNIQUE. 



723 



A pair of solder tweezers of the size and shape shown in Fig. 589, 
should be use for picking up the pieces of solder, and its points should 
be kept clean and out of the soldering flame in order to be in proper 
condition to use. 

For cutting the solder into convenient sizes, a pair of small shears 
with especially strong blades, such as is illustrated in Fig. 590, is es- 
pecially adapted for use at the operating bench, being preferable to the 
larger laboratory shears for the purpose. 

A number of years ago, the author devised a set of delicate clamps 
for the approximation of the various parts of bands and appliances 
while being united with solder, and the ten years of constant use and 
improvement have brought them up to a standard of perfection which 




Fig. 590. 



makes the operation of soldering extremely simple, accurate and 
rapid, as well as saving in time, patience, and nerves from the old 
finger method. 

There is hardly a single practical combination of appliance parts 
that cannot be perfectly adjusted in these clamps, the original set of 
which is shown in Fig. 591. 

The Magill Band. — One of the most important adjuncts to the 
direct application of force to the upper and lower ten anterior teeth, 
is the Magill band, or plain band as it is sometimes called. 

It may be constructed of gold, platinum, iridio-platinum, plati- 
nized gold, gold alloyed with platinum, or German silver according 
to the particular qualities desired. The author prefers the iridio- 
platinum, constructed of sheet iridio-platinum of about 36 gauge, 
B. & S., and the platinized gold band of the same gauge. 

The construction of the Magill band in the precious metals is 
similar to that in German silver except that the gold solders of varying 
grades are used in the former. 



724 



ORTHODONTIA. 



German silver band material may be found at the depots in three 
thicknesses, according to the degree of strength required, being fur- 







Fig. 591. 



nished in coils, convenient for ready use, which represents that which 
is sold with the Angle appliances. The heavier or thicker form of 
band material is used where great strength and durability is required, 





Fig. 



592. 



as for cuspid and bicuspid bands, and for retention; the thinner 
material where strength and durability may be sacrificed for incon- 



CONSTRUCTIVE TECHNIQUE. 



725 



spicuousness and neatness of appearance and fit, as in the banding 
of lower incisors, and for temporary retention. 

The band material should first be formed into a loop with the 
fingers, and the two sides of the loop forced between the mesial and 
distal approximating surfaces of the 
tooth to be banded and the adjoining 
teeth, forcing it well up toward the 
gingivae, and after pulling it taut on 
the lingual surface, pinching the ends 
of the loop together close to the tooth 
surface, as at A in Fig. 592, with the 
Angle band forming pliers, shown in 
Fig. 593. The ends of the band ma- 
terial should meet at right angles at the 
point of union, so as to form a contin- 
uous inner surface of the band when 
soldered, as in B in the same cut. 

The Magill band should not be 
fitted too closely to the tooth surface, 
for some looseness is necessary to pro- 
vide space in order to contain the 
cement in sufficient bulk for proper 
fixation of the band and protection of 
the tooth surface. The burnishing of 
the margins of the band may be done 
after it is in position and the cement 
still soft. A slight trimming of the 
upper mesial and distal margins so as 
to not encroach upon the gum tissue is 
permissible. 

Oftentimes, especially in the case of 
the cuspid band, it is advisable to 
unite the band upon the labial surface 
of the tooth, a notch in the projection 
of the united ends making a convenient 
spur for the arch to rest in or for the 
ligation of the cuspid when in infra- 
occlusion, etc. 

Soldering The Band. — In uniting the ends of the Magill band with 
solder, they should be held by a No. 1 soldering clamp, and a piece 
of solder one-eighth of an inch square placed in the seam, where it is 




Fig. 593. 



7 JO ORTHODONTIA. 

held in position by the pressure of the clamp, as in Fig. 594, and after 
touching the wax stick to the slightly warmed seam so that a small 
portion of the flux is melted into it, the ends to be united should be 
held in the needle flame of the blowpipe until fusion occurs. The 
surplus ends are next cut off, and the ridge which remains polished 
smooth with the sandpaper disc, after which the band is transferred 
to a boiling solution of alum to deoxidize it, and then polished and 
plated. If it is not to be cemented on at once, it should be properly 
ticketed and filed until the next sitting. 




Fig. 594. 

Accessories to the Magill Band. — As the Magill band is usually 
utilized for the more direct attachment of ligatures, and for retaining 
appliances, as well as for lever tubes and traction screw tubes, the 
various methods of making these attachments should be carefully 
studied. Where the banded tooth does not need rotation, but simply 
a direct movement toward the arch, a notch in the seam of the band 
will prevent the ligature from slipping, as in A, Fig. 595. 

Lingual spurs for rotation may be attached as in B and C, Fig. 
595, the pinhead spur being soldered with the No. 5 pinhead clamp 
of the set of soldering clamps, the clamp itself requiring the use of but 

tiSik fgpj |®| (aii^ gjffllfri 
A B G D E F 

Fig. 595. 

one hand, as it automatically holds the pinhead in exact position at 
any desired point on the band. 

For soldering on wire spurs the procedure is somewhat different; 
the band should be held in a No. 1 clamp in the left hand, and a length 
of spur wire which has a ball of solder attached to its end adjusted 
with the right hand, the third fingers of each hand touching so as to 
give support and steadiness while the parts to be united are held in 
the flame. 

The retaining spurs shown in E, Fig. 595, are attached very similarly 
to the ligature spurs, except that the wire is held against the band 
lengthwise, with the right hand, the surface of the band having had 



CONSTRUCTIVE TECHNIQUE. 727 

a small piece of solder about one-eighth of an inch square fused upon 
it previously. 

The lever tube, in D, Fig. 595, is cut off the desired length and 
held in approximation with the surface of the band by the No. 3 
clamp alone, or the band may be held by No. 1 clamp, while a long 
piece of lever tubing is attached with solder to the band surface and 
afterwards cut off and polished. 

Larger sized tubing for the ends of the traction screw, as at F 
Fig. 595, may be adjusted to position with the Nos. 2 and 4 clamps, 
as illustrated in the photograph in Fig. 591. The short tubes may be 
held in the tip of the No. 4 clamp at any desired angle to the band 

while being soldered, being especially useful in , , — 

the attachment of the tube at one corner of a l=> 

cuspid band for the end of the traction screw. 

Spurs and Hooks for Expansion Arch. — 
For convenience in use, and saving of time at 
the chair, a number of pieces of iridio-platinum, 
platinous gold or German silver wire of two «V L 

different sizes, 18 and 21 gauge, B & S, about FlG ' 5g6 ' 

four or five inches long, should be made up, having a ball of solder 
attached at both ends. 

The spur for the expansion arch should preferably be made of the 
21 gauge wire, as it does not need to extend as far from the surface 
of the arch as a spur of larger diameter. 

If made of German silver, a piece of band material is first bent 
around the arch, forming a loop, to the convex surface of which the 
spur wire is soldered, as in K, Fig. 596. The band material is then 
trimmed down so that it will encircle about one-half of the circum- 
ference of the arch, and after polishing the concavity of the half 
cylindrical piece, with the sandpaper disc, a small portion of soft 
solder is melted into it, fluxing with phosphoric acid, and then it is 
united to the clean surface of the arch at the desired point. In fusing 
the soft solder, the parts should not be held in, but above the flame, 
so as not to take the temper out of the expansion arch. 

The hook for the attachment of rubber elastics to the arch, is 
constructed in a similar manner, bending it into a hook and finishing 
the point so as to avoid irritation, after soldering it to the arch, as illus- 
trated at L, Fig. 596. 

In making a hook for a platinous gold arch, a piece of 21 gauge, 
B & S iridio-platinum or platinous gold wire may be soldered directly 
to the expansion arch with an 18k gold solder and afterward bent into 



728 



ORTHODONTIA. 



hook form and cut off the requisite length, the temper of the arch not 
being affected by this process. 

Assembling the Parts of Molar Clamp Band. — The molar clamp 
band is made up of a short piece of band material, and a lingual 




Fig. 597. 

screw passing through a short tube soldered at one end of the band, 
adjusted with a nut turned upon the lingual screw. 

Although it is not essential that the operator make his own clamp 
bands, it is often necessary that he reconstruct clamp bands which 
have broken under some unusual stress. 



r\ 






1 
1 

1 





Qbsbbbssbbe 



T£T 



Fig. 598. 



r\ 



bA 



TJ 



For easily and quickly soldering the band and the lingual screw, 
the author makes use of a special clamp, illustrated in Fig. 597, which 
holds the two parts in adaptation during the soldering operations. 
The solder and flux are always placed between the parts to be united 
before placing in the flame. 



CONSTRUCTIVE TECHNIQUE. 



729 



The short tube is held in apposition with the other end of the 
band with a No. 2 clamp of the set previously described, as in Fig. 591. 

The band is formed in a circle, the screw thrust 
through the lingual tube and the nut adjusted to it, when 
it is ready for the attachment of the buccal tube. 

Soldering Buccal Tube on Molar Clamp Band. — 
This operation is one that is frequently done and requires 
so much exactness that the aid of special clamps is almost 
indispensable to facilitate rapid and correct soldering of 
these parts. 

Almost two-thirds of the " German silver" molar bands 
purchased at the depots have to be subjected to a change 
in the position of the tube so as to secure proper align- 
ment of the arch wire, see Fig. 424, and to look attractive, 
must be replated before placing in the mouth. 

During the treatment of Class II and III cases, the 
tipping of the anchor teeth distally and mesially requires a 
realignment of the anchor tubes occasionally to keep up 
the efficiency of the anchorage. To prevent the expan- 
sion arch from dropping below the edges of the incisors, 
as at A, Fig. 598 in a Class II case, the anchor clamp- 
bands should be removed and the buccal tubes realigned 
so that the expansion arch will rest upon the surfaces of 
the incisors as at B, Fig. 598. 

The technique of this operation is as follows: 

The molar clamp band is held in a vice like grip in 
the dog jaw of special clamp No. 6, Fig. 599, on the 
opposite side from the threaded wire extension with nut 
as to enable this clamp to be held in the fingers of the 
left hand, while those of the right control clamp No. 7, 
which engages the buccal tube, with the sheath end 
toward the handle of the clamp. 

Having previously fastened a piece of solder about 
one-eighth of an inch square on the buccal side of the 
surface with the wax flux, at the point at which the tube 
is to be joined, and placed some of the wax flux on the 
center of the side of the tube, the right angle arm of the 
No. 7 clamp is placed on the lingual side of the band, 
and the arm holding tube is allowed to drop down into Fig. 599. 
position on buccal surface of the band, pinning the solder and flux 
underneath. The tube is aligned horizontally with edge of band, and 




730 ORTHODONTIA. 

then the clamp band and tube are held in the flame of blowpipe until 

solder flows perfectly. 

The Pivotal Anchor Tube.— It will be found valuable to solder 

a short piece of 14 gauge, B & S round wire between the buccal 

tube and the clamp band, as in Fig. 600, forming a pivotal anchor tube, 

which possesses sufficient strength for the 
support of the arch under all conditions, 
and at the same time will allow of sufficient 
change of inclination of the anchor tube by 
upward or downward twisting, with a pair 
of pliers for any arch alignment desired, 

doing away with the necessity of removing cemented bands and 

unsoldering the anchor tubes to realign them. 

The short piece of wire should be of German silver for the German 

silver clamp band and of platinum for the gold clamp band. 

X. PLASTER TECHNIQUE. 

Necessity for Accurate Models.— The primary importance of 
diagnosis in the consideration of the possibilities of treatment of 
malocclusion, renders it necessary that accuracy in the models of the 
teeth should be an essential feature. 

The casts of each dental arch in occlusion should represent, to 
the minutest degree, the exact variation of the occlusion from the 
normal, the depth of cusps and length of overbite, the compensating 
curves, and separately should exhibit all the fine lines of the anatomical 
structures which it is intended they should copy, such as the rugae and 
stipples of the gum tissue, the form and attachment of the frenum 
labium, the height and width of the palate, abscess, fistulas, and 
pathological conditions such as hypertrophy of the gingivae, the 
degree of development of the arch well up to the line of demarcation 
of the check and gum tissue, and especially the perfection or imper- 
fection of every tooth surface, including developmental grooves and 
inclined planes, and the facets of the cusps, which latter, to the ex- 
perienced eye, tell a story, which can be learned in no other way, of the 
articular movements of the mandible. 

Reference to the model during and after treatment of a case is 
of value in indicating the changes in development of the alveolus, and 
the influence of inclined planes in determining normal cusp relation- 
ship when working in harmony with normal sized arches and normal 
occlusion and articulation. 

A collection of finely made models serves not only as a library 



PLASTER TECHNIQUE. 731 

of reference and study, but also as an accurate indication of the 
individual skill of the operator, both in the making of the models 
themselves, and in the perfection of treatment which they exhibit. 

Were the laity possessed of sufficient knowledge of the possibilities 
of treatment of malocclusion, they might, by comparison, choose the 
more expert orthodontist by the results which are exhibited in his 
model collection, which, to a degree, show his skill, his experience 
and his artistic ability. 

The model serves as a guide to arch determination and indicates 
the proper relations of retaining appliances upon completion of the 
treatment. 

Medico-legally, the plaster reproduction of the teeth in the model 
is an accurate record of fact, which is accepted as evidence in a court 
of law, thereby ensuring some protection to the operator from the 
unappreciative and dishonest who resort to questionable methods in 
the evasion of their just obligations. 

Impression Materials and Methods. — Plaster-of-Paris has long 
been recognized as the ideal material for taking accurate impressions 
of the teeth, casts from which are absolutely accurate in detail of re- 
production, as in surgery, its use in the reproduction of internal or 
external structural anatomy has not been superceded by any other 
material. 

Dr. E. H. Angle was the first to place model making in the list of 
the arts by the introduction of a method, which in its main char- 
acteristic, is still followed, the improvement in technique and detail 
which have been suggested by others in the same field being here 
described. 

As the impression in plaster will reproduce the finest lines of tooth 
surfaces, care should be taken that all hard and soft deposits be 
removed, and the teeth thoroughly cleaned before the impression is 
taken. 

The Impression Tray. — The Angle impression trays, illustrated 
in Fig. 601, are especially adapted for taking full impressions of either 
arch, having high rims, and being so shaped and polished that they 
may be removed soon after insertion in the mouth by a slight manip- 
ulation, leaving the setting plaster in the mouth to be sectioned and 
fractured and removed in several pieces. 

Trays should be selected according to the size of the mouth, large 
enough to allow for at least one-eighth of an inch of plaster between 
the teeth and the sides of the tray, which will admit of a slight bending 
for' such adaptation. 



732 ORTHODONTIA. 

These trays are provided in graded sizes 21, 21^-, 22, 22^-, and 23 
in the upper set, and in corresponding sizes 24, 25 and 26 in the lower 
set. A few more intermediate sizes are still desirable. 

The surfaces of the impression trays should never be scratched or 
indented, as any marring of the surface prevents easy removal of the 
tray from the impression in the mouth. It will be found an economv 




no. 001. 



of time and money to replace slightly marred trays with new ones 
from time to time. 

Mixing of the Plaster.— On account of the quick setting of im- 
pression plaster, the use of salt or potash for hastening this process 
is unnecessary in the plaster mix, in fact, they are detrimental to 
the securing of a perfect impression because of the haste necessary in 
manipulation, and the coarseness of crystallization of the plaster, 
which is destructive of the fine lines on the surface of the impression. 



PLASTER TECHNIQUE. 733 

Distilled water at a temperature of about 70 F. is preferred for 
obvious seasons. 

The quantity of water necessary for the usual mix should be some- 
what accurately gauged, and the plaster gradually sifted in until it 
absorbs the water completely, when it is ready for immediate pouring 
into the tray which has been selected a little larger than the arch of 
which an impression is desired. 

Only the best impression plaster should be used, French's plaster 
as furnished by the depots in a metallic can with tightly fitting cover 
being preferable, as it may be kept perfectly clean and dry in this 
receptacle. 

Distribution of Plaster in the Tray. — If the impression is to be of 
an upper arch, the palatal portion of the tray should not be covered 
with the plaster, the rest of the tray being about three quarters filled, 
and a small surplus allowed to rest upon the handle to be forced under 




Fig. 602. 



the lips. If necessary, the buccal and labial spaces may be first filled, 
using a bone or glass spatula to carry the plaster to place, as suggested 
by Dr. A. P. Rogers. 

The tray is then inserted in the mouth, and pressed quickly into 
position, taking care that the teeth are about equally distant from 
either side and the bottom of the tray. While being held in position 
with the middle finger of the left hand, the surplus plaster may be 
cleaned from the tray with the tweezers and cotton. 

The impreession should be allowed to harden until it will fracture 
properly, when the tray should be removed by exerting a slight and 
uniform downward pressure upon the handle, and surplus pieces 
removed from the mouth with the tweezers and cotton. 

The impression should next be grooved vertically, usually over the 
cuspid region, on both sides with the knife shown in Fig. 602, which 
is best adapted for reversal in grooving both upper and lower im- 
pressions without danger of cutting the lips, the short curved blade 
being admirably shaped for skillful manipulation. 

By prying from the bottom of one of the grooves with this same 
knife, after the plaster is hard, the central section of the impression 
may be removed easily, and the two buccal portions by exerting an 



734 



ORTHODONTIA. 



outward prying motion with the thumb against the anterior edge, 
leaving the palatal portion to be gently pried out with an instrument. 




Fig. 603. 

The pieces are then placed in a small box upon which is marked 
the name and date and age to be copied later upon the posterior 
surface of the cast. 




Fig. 604. 



The lower impression differs from the upper only in the detail of 
the manipulation of the tray, care being taken not to allow of an excess 
of plaster in the distal ends of the grooves. 



PLASTER TECHNIQUE. 735 

Figs. 603 and 604, loaned by Dr. Rogers, represent very perfect 
lower and upper impressions of the teeth after the fractured pieces 
have been assembled. 

Assembling the Impression. — The fractured pieces should be 
thoroughly dried, over night usually, although they may be quickly 
dried by placing them upon a piece of tin over a burner, and then 
assembled, beginning with the larger pieces, adding one at a time, and 
dropping a small bead of hard sticky wax upon the outside of the 
impression at intervals of about one-quarter of an inch along the lines 
of fracture, as illustrated in Fig. 605. The edges of the fractured 
pieces should be cleaned of crumbled pieces before uniting them. 




Fig. 605. 

Occasionally, it will be of advantage to replace broken pieces in the 
tray but, as a rule, better results are obtained without doing so. 

Varnishing the Impression. — After being properly assembled, 
the impression should be varnished with a solution of shellac allowed to 
dry for half an hour, and then varnished with a solution of sandarac, 
repeating the last varnish again in another half hour. These solutions 
are so thin that they do not leave any perceptible coating upon the 
surface of the impression, although rendering it easily separated from 
the cast, the shellac giving a color line to cut to, and filling the pores, 
and the sandarac simply filling over the surfaces of the pores, so that 
capillary attraction cannot take place.* 

. *According to Angle, these solutions should be prepared in the proportions of i ounce 
of shellac to 3^ ounces of alcohol, for the shellac varnish and i ounce of sandarac to 2$ 
ounces of alcohol for the sandarac varnish. 






ORTHODONTIA. 



Filling of the Impression.— The varnishes being thoroughly 
dried, the impression may be placed in a basin of clean water to 
become infiltrated from the outside with water, while the plaster is 
being mixed ready for its pouring. 

A slow setting model plaster is preferred for the cast, although 
many have used the impression plaster with good results, its fineness 
giving a very beautiful surface. 

The plaster should be mixed in the same manner as for the impres- 
sion, and a small portion placed in the heel of the impression and 
carefully worked forward from one tooth cusp to another with the 
camel's hair brush, until all the cusps are perfectly filled, when the 
remainder of the impression may be quickly filled with the plaster 
knife, which should be of platinoid so as to prevent rusting. 

A large portion of the plaster should be placed upon a clean glass 
slab and the impression inverted thereupon, and pressed down so that 




Fig. 606. 

the anterior edge is within one-half inch of the glass surface, preserving 
a parallel between the bottom of the impression, or tray, if present, 
and the horizontal line of the glass slab, as in Fig. 606. The surplus 
plaster is then trimmed away with the plaster spatula, and the plaster 
allowed to harden for about twenty minutes before it is ready to be 
again touched. 

Sectioning and Removal of Impression. — The impression is 
more easily removed from the cast within half an hour from the time 
of its filling, as it then contains the greatest amount of moisture. 
However, it should be immersed in water again for a few seconds to 
still further soften the surface before attempting to separate the im- 
pression from the cast. 

The small beads of wax should be cut off and the portion of the 
cast extending above the impression roughly trimmed with the larger 
of the two plaster knives shown in Fig. 607, to approximately the shape 
to which it is intended to conform when finished. 



PLASTER TECHNIQUE. 737 

The sides of the impression may then be vertically and horizontally 
grooved as in Fig. 608 using the smaller knife shown in Fig. 607, the 
two knives being suggested by Dr. Rogers. 

The depth of the grooves should not be greater than the brown 
color of the shellac varnish, which appears as the bottom of the groove 
approaches the surface of the cast. 




Fig. 607. 

Beginning at the heel of the impression, one section at a time is 
pried away with the grooving knife, removing the upper sections first. 

The author prefers to shave down the surface above the occlusal 
surfaces of the teeth until the brown color above the prominent tooth 
cusps begins to appear before making the vertical and horizontal 




Fig. 608. 

grooves in most cases, and many times a single vertical groove in the 
region of the cuspid on each side is sufficient for the easy removal of 
the sections extending from these grooves to the heel of the impression. 
The front of the impression should almost always be horizontally 
grooved to prevent accidental injury to the cast in removal. 

Oftentimes, the lines of fracture, which may run along the cusp 
47 



73« 



ORTHODONTIA. 



surfaces of the teeth, will facilitate the removal of the impression very 
materially. 





Fig. 609. 

It will almost always be found necessary to groove the lingual 
surface of the impression upon a lower cast before it is possible to 
remove it. 



PLASTER TECHNIQUE. 



739 



In an upper impression also, it will often be necessary to make 
a groove lengthwise of the palatal section of the impression and then 
remove one-half of the palatal portion at a time. 

It is well to mark on the surface of an impression, before pouring, 
the positions of teeth in labial or lingual occlusion, to prevent marring 
them in the sectioning process. 

Trimming of the Model. — After the removal of the casts from the 




Fig. 6io. 

impressions, they should be moistened in clean water, and then roughly 
trimmed to the geometrical outlines which have been accepted as most 
artistic and harmonious for each cast, the base, for the lower cast, 
being carved to the design at the top of Fig. 609, with slightly rounded 
front, and the upper cast, to the pattern at the bottom of this figure, 
being precisely similar, except for the pointed front, which not only 
affords extension for a frenum labium of varying sizes, but gives a 
pleasing and distinctive variation to the capital of the model. 




Fig. 611. 



From a geometrical standpoint, the two patterns present the forms 
of two triangles with equiangular basal angles which have been clipped 
by lines parallel to the lateral lines of the triangle from one-quarter to 
one-half an inch in length, and the anterior angle cut across from inter- 
sections directly over the cuspids on the lateral dimensions by the curve 
on the lower cast and the obtuse angle on upper cast. 

Constructed upon these lines, the base and capital present almost 



740 ORTHODONTIA. 

similarly formed designs, with the long sides of the triangles parallel 
to the buccal surfaces of the bicuspids and molars, and the median 
line of the anterior sections equidistant from the cuspids, except where 
there is much divergence of the anterior teeth mesially or distally, when 
the median line of the capital may be made to coincide with the central 
line of the cast as indicated by the rugae. 

Proceeding first with the rough approximation of these patterns 
with a broad bladed plaster knife of hardened steel and an edge so 
sharpened that the flat surface of the blade is a perfect plane on either 
side, as in Fig. 610, the lower cast, or base of the model, should be so 
earved that the plane of the occlusal surfaces- of the teeth should be as 
nearly as possible parallel to the horizontal. 




Fig. 612. 

In cases in which the compensating curves are very marked, the 
plane of occlusion might be represented by the plane passing through 
or touching the tips of the distal cusps of corresponding molars on 
either side and the edges of the central incisors. 

The under surface of the base of the model should be evened with 
a small plaster plane having a very sharp blade as is shown in Fig. 612, 
representing the Angle plaster plane. The angles which the anterior 
and lateral planes make with the base should all be right angles, and 
the planes which they enclose will then all be vertical ones. 

The thickness of the mechanically finished portion of the cast is 
determined somewhat by the size of the anatomical portion, but should 
seldom, in a cast of the permanent teeth, be less than one-quarter of an 
inch in the height of the anterior vertical planes. 

After the lower cast is properly aligned and finished to form the 



PLASTER TECHNIQUE. 741 

base of the model, the upper cast is cut to approximate the pattern 
shown on the right in Fig. 609, and is then placed in occlusion with the 
base so that all surfaces and angles of the capital may harmonize with 
those of the base. 




Fig. 613. 



The upper surface of the capital should be planed down until it 
is parallel with the horizontal, unless it is too thin, in which case the 
required thickness may be secured by inversion of the occluded model, 
capital downward, upon a small quantity of fresh plaster upon a glass 




Fig. 614. 

slab, it being necessary only to manipulate the model so that the base 
of the model will be in the horizontal plane as judged by the eye. 

The planes of the sides of the capital should be all vertical planes, 
and the posterior vertical planes should coincide, if possible, giving 



74- ORTHODONTIA. 

an accurate guide to the occlusion if it should not have been marked 
on the cusps, as shown in Fig. 612. 

The small brass plane with bronze blade, illustrated in Fig. 611, is 
very useful for trimming model surfaces, especially as much more 
accurate surfaces can be made with it than with the knife. 

The mechanically finished surfaces of the model may be made still 
smoother by finishing with a fine broad, flat, jeweler's file after the 
casts are perfectly dry, as suggested by Dr. A. P. Rogers. 

A slight bevel cut around the entire edge of both capital and base 
adds to the artistic finish, and preserves the model from chipping of 
otherwise sharp angles in handling. 

The trimming of the capital and base according to certain definite 




Fig. 61 



geometrical lines, is not only the most artistic and best proportioned 
conformation of otherwise ungainly reproductions, but it serves the 
very practical purpose of a standard for uniformity which enables 
the busy orthodontist to more quickly and consecutively follow out 
the definite rules for obtaining esthetic effects than by the old and less 
accurate methods of model trimming. 

The anatomical portions of tbe model should represent perfectly 
the parts which they are intended to reproduce, and will be perfect in 
proportionate degree to the care which has been taken in the consecutive 
steps of its production. 

Marking and Numbering of Models. — When such infinite pains 
have been taken and artistic skill used in securing a beautiful and har- 
moniously proportioned model, it should not be ruined by marking the 



PLASTER TECHNIQUE. 743 

name of patient, the age and the date of commencement of treatment 
upon every surface of the mechanical portion, as is often done. 

Each model needs its serial number for the cabinent, which may be 
marked with india ink upon the labial surface of the base of the model 
and the posterior surface of the capital, leaving all other anterior 
surfaces of the model void of any marks whatever. The name, date, 
age, etc., may be noted on either of the posterior surface of the capital 
or base. 

In numbering, it is advisable to select alternate odd numbers for 
treatment models, leaving the alternate even numbers for the after- 
treatment model. 




Fig. 616. 

Repairing Defects. — If a good impression has been first secured 
and the detail of assembling of the fractured portions, the varnishing, 
pouring and removal of the cast, carried out according to the instruc- 
tions previously given, very little, if any, retouching will be necessary 
upon the anatomical portion of the cast. 

But, at least, the amateur is liable to get a few air bubbles or other 
imperfections upon the surface of some of his casts, which will need 
some little skill in the use of the camel's hair brush to render them un- 
noticeable. 

Air bubbles and other indentations such as are often caused by 
the knife blade in separating, are filled with plaster in the following 
manner: First, moisten the cast or the portion of it needing repair, 
then with the camel's hair brush carry a small quantity of very thinly 
mixed plaster into the bottom of the air bubble, repeating until it is a 



744 



ORTHODONTIA. 



little more than full, when the correct contour is obtained by a twisting, 

wiping motion of the slightly moistened brush over the surface. 

Fig. 613 represents an upper cast which has a consider- 
able number of air bubbles caused by carelessness in pour- 
ing the impression, and the loss of contour of some of the 
cusps of the teeth make the cast rather unsightly. A little 
practice with the brush and plaster will enable the operator 
to restore the contour as in Fig. 614, which illustrates the 
same cast as in the previous figure after it has been treated 
by this method. 

Fractured teeth and cusps are somewhat differently 
treated, since it is almost impossible to force plaster of any 
consistency into a crack such as is visible on adjusting two 
fractured portions of a tooth together. 

One of the surfaces of the fracture should be carved out 
to a crescent shape, not touching the periphery of the cusp 
or tooth, however, as this will be needed to place it in 
register, after which the groove thus made may be filled 
with thin plaster in the same manner as the air bubbles. 
This method of uniting fractured pieces is very artistic in 
effect and the result permanent, being preferred to cement 
which causes a line of demarcation which is especially 
noticeable in a photograph. 

Fig. 615 represents a badly fractured cast, the right 
cuspid, both centrals, and the left lateral having been 
accidentally broken off. Fig. 616 exhibits the same cast 
after the fractured pieces have been reunited by this method. 
The right central was restored in contour entirely with the 
brush, since the fractured portion was lost. It is possible 
to restore even such a delicate part as the frenum labium, 
w r hich seldom escapes fracturing in separating, but a knowl- 
edge of the minute anatomy of the parts is essential to the 
attainment of artistic and esthetic results in attempting the 
reproduction of lost portions of the anatomical part of 
the cast. 

The lines of fracture of the impression are reproduced 
in the cast, and should be carefully burnished down with 
the spoon blade of a wax spatula adapted for the purpose, 

such as is illustrated in Fig. 617, being an S. S. White No. 7 double 

bladed spatula. 

The smaller blade may be sharpened upon one edge to be used in 



Fig. 617. 



PROPHYLAXIS. 



745 



removing any superfluous plaster contiguous to the festoons of the gums 
on the cast, also in carving out any surplus plaster from the embrasures 
of adjoining teeth, and the cusps of bicuspids or molars which are im- 
perfect. Any attempt at carving beyond the shaving of superfluous 
plaster, quickly shows its artificiality and should be avoided. 

XI. PROPHYLAXIS. 

During the wearing of appliances in the mouth, the greater liability 
of food collecting around the teeth, and the lessened activity of the oral 
fluids in performing their natural cleansing function makes it impera- 
tive that especial prophylactic measures be instituted. 

The patient's teeth should be thoroughly cleaned before the com- 
mencement of operations, and during treatment instructions should be 
given for the frequent use of the tooth brush, preferably after each meal 
and upon arising. 




Fig. 618. 

A tooth brush with one row of bristles, called the Rolling Tooth 
Brush,* shown in Fig. 618, is much better adapted to cleansing above 
and below the expansion arch than the brush with several rows of 
bristles. 

Occasionally, the expansion arch should be removed, and the teeth 
cleansed carefully with pumice and the rubber cup. It is of still 
greater benefit to have the patient referred back to the family dentist 
for more detailed prophylactic treatment, especially with the orange 
wood stick and pumice. 

The compressed air spray in connection with antiseptic mouth- 
washes, is most beneficial in these conditions, being used at each visit 
of the patient throughout the treatment. 

Dr. H. C. Ferris has recently recommended a combination of sprays 
which have certain peculiar reactions which make them of exceptional 
value, being both chemical and mechanical in their action. 

The first of the series of sprays contains the active agent iodine 
in combination with potassium iodide, which acts germicidally to de- 
stroy the spores and parent cells in albuminous material, which it read- 
ily penetrates, staining the bacterial plaques so that they are visible upon 
tooth surfaces. 

* Manufactured by the Rolling Tooth Brush Co., Boston, Mass. 



746 ORTHODONTIA. 

The second spray consists of a starch solution which absorbs the 
stained plaques, forming a flocculent precipitate, which is readily 
removed by the third spray which is a simple solution of sodium car- 
bonate, having the power to decolorize the precipitate previously 
formed, at the same time freeing the surfaces of the teeth still further- 
by saponifying the fats. 

The antiseptic and beneficial value of these sprays, used consecu- 
tively, is not excelled by any other at present known methods of oral an- 
tisepsis. 

The series of sprays are given below in the order of their use, it 
being necessary to have separate nozzles for each spray, which also 
must be used at the temperature noted in order to have the desired 
effect. 



I^ — Iodini, n\ xxx. 

Potassii iodidi, n^ xix. 

Aquae dest. ad. q. s. § iv. 

Sig. — To be used in spray under high pressure 
at the temperature of 98 F. 

II. 

1^ — Starch, gr. xxxviii 

Aquae menth. pip. B iv. 

Oleum menth. pip. n^ xx. — M. 

Sig. — To be used at the temperature of 115 F. In making 
this compound, mix the first two ingredients and let stand for 
five minutes, then boil for five minutes, then add the flavoring. 

III. 

~ty — Sodii carb., gr. xxxviii. 

Aquae gaultheria, 5 iv. 

Olei gaultheria, n^ xxx. — M. 

Sig. — To be used at the temperature of 115 F. 



INDEX 



Guide to the Index. — The index has been arranged with a view to direct the reader to his subject 
without delay. All readers do not think of the same subject matter in the same form, therefore the 
same subject will be found indexed in various forms. For instance: 
"Preparation of cavities:" 

"for fillings, 161" 
"Cavities:" 

"preparation of, for fillings, 161" 
"Fillings, preparation of cavities for, 161" 
Where a — appears before a line it indicates that the indexed line relates to the sub-heading 
above it. 



Abnormal arch development, 527 -~~"""* 
Abnormal frenum labium, 547 

operation for, 603 
Abscess, acute alveolar, 352 

chronic alveolar, 354 

pericemental, 362 

pocket, secondary, 361 

with sinus, 354 

without sinus, 354 
Absorbed root, 360 
Absorbents, the use of, 157 
Accessories to the Magill band, 726 
Adaptation of the arch, 583 ^- — 
Adenoids, 539 

Adjusting the rubber dam, 148 
Adjustment of anchor clamp bands, 588 
Advantages of early treatment (ortho- 
dontia), 609 
Adventitious growths, removal of, 541 
After-pains of extraction, 434 
After-treatment of extraction, 435 
Alveolar hemorrhage from the extraction 

of a tooth, 432 
Amalgam, 240 
Amalgam and cement, 252 
Analgesics, 222 

Anatomy of the human teeth, 1 
Anatomical parts of the teeth, 2 
Anchorage: 

first molar, 577 

intermaxillary, 578 
uses of, 579 

occipital, 580 

primary, 577 

reciprocal, 573 

re-info reed, 573 

requirements, 611 

secondary, 578 

simple, 573 

summary of principles, 581 
Anchor clamp bands, adjustment of, 588 

teeth, bodily control of, 585 

tube, the pivotal, 730 

tubes, adjustment of, bucco-lingual, 

589 
Anesthesia, local, 385 



Anesthetization and devitalization of pulps, 

3*7 

for removal of pulps, 318 
Anesthetizing the pulp, method of, 396 
Angle of the tooth, 2 
Anodynes, 222 
Antagonizing spurs, 713 
Anterior and posterior arch retention, 711 
Antrum, 361 
Apex, 2 

Apical foramen, 2 
Appliances: 

choice of metals for (orthodontia), 717 

efficiency of (orthodontia), 572 

materials for construction of (ortho- 
dontia), 717 
Arch: 

development of, 505 

integrity, preservative forces of, 511 

predetermination, 554 

retainer, lingual, 710 
Arches: 

case reciprocating, 576 

of temporary teeth, 506 
Arrangement of light in the operating room, 

85 
Arrested developmental conditions in the 

arches, early treatment of, 606 
Arsenical poisoning, 332 
Articulation, 513 
Artificial roots, 449 
Asepsis in the operating room, 89 
Assembling the impression (orthodontia), 

735 
parts of molar clamp band (ortho- 
dontia), 728 

Assistants in the office, 490 

Associated anatomical structures, develop- 
ment of, 514 

Badlv decaved root, 351 
Band: 

accessories to the Magill, 726 

assembling parts of molar clamp, 7 28 

driver, 589 

Magill, 723 



747 



748 



INDEX. 



Band: 

soldering the, 725 

soldering buccal tube on molar clamp, 
729 
Bands, plain, 719 
Beauty, physical relations of, 517 
Bibs, 156 
Bicuspids: 

lower first, 27 

— buccal surface, 27 
— cervical margin, 29 
— distal surface, 29 
— lingual surface, 27 
— mesial surface, 29 
— occlusal surface, 27 
— pulp cavity, 30 
— root, 30 
second, 30 
upper first, 19 

— buccal cusp, 19 
— buccal surface, 20 
— cervical margin, 23 
— distal surface, 22 
— lingual surface, 21 
— mesial surface, 22 
— occlusal surface, 19 
— pulp cavity, 23 
— root, 23 
second, 24 
Bilateral infra-occlusion of bicuspids and 

molars, 553 
Blood-vessels of the pulp, 82 
Blowpipe, the Kerr, 720 
Bodily control of anchor teeth, 585 
Bonwill's diagram, 553 
Bromids, 222 
Buccal cavities, 268 
Bucco-lingual alignment of anchor tubes, 

589 
Burs, 181 

Cabinet, the dental, 91 

Calculus, 108 

Capping the pulp, 312 

Card system, 497 

Caries, pathology of dental, 117 

Casualties attending tooth extraction, 431 

Causes and treatment of discolorations of 

teeth, 367 
Cavities: 

division of, 164 

examination of teeth for discovery of, 

127 
fissure, 166 

instruments for preparation of, 178 
management of large proximo-occlusal, 
in pulpless bicuspids, 212 
large, in pulpless molars, 212 
nomenclature, 161 

of internal parts of, 163 
preparation of, in bicuspids and molars 
involving the occlusal surface, 207 
— buccal and labial, 268 
— for fillings, 161 
— for inlays, 267 
— for restoration of incisal tips, 272 



Cavities : 

preparation of simple proximal cavities 
in incisors and cuspids, 270 
— in occlusal surfaces of bicuspids 

and molars, 275 
— involving the proximal and occlusal 
surfaces of bicuspids and molars, 

2 73 
— proximal cavities involving the in- 
cisal angle, 270 
— proximal in incisors and cuspids 
involving incisal angle, 198 

steps in formation of, 164 
Cement, 246 

for inlays, 288 
Cemental fusion of roots, 431 
Cementoblasts, 82 
Cementum, 72 
Central incisor, lower, 10 

upper, 3 
Cervical clamps, 154 

Characteristics of normal occlusion, 509 
Chemical constituents of enamel, 62 

— composition of saliva, 99 
Chemistry of pulp decomposition, 341 
Children's teeth, treatment of, 377 
Chisels, 179 
Chloroform, 222, 223 

Choice of metals for appliance (orthodon- 
tia), 717 
Chronic alveolar abscess, 354 
Clamp bands, adjustment of anchor, 588 
Clamps, 153 
Classification of cavities, 162 

chart (orthodontia), 550 

malocclusion, 548 -" 
Closing up spaces between incisors, 597 
Coagulating agents, 347 
Cocain, 219 

hvdrochlorid, 390 
Cold, 217 
Combination fillings, 251 

amalgam and cement, 252 

cement and gutta-percha, 253 

gold and amalgam, 252 

gold and cement, 252 

gold and tin, 252 

platinum and gold, 251 
Comparative measures of resistance (ortho- 
dontia), 573 
Complications incident to removal of pulp, 

" 33° 

in treatment after extraction of teeth, 
694 
Conditions necessitating removal of pulp, 

3i7 
Construction of gold inlays, 301 

difficult cavities filled by the Taggart 
method, 304 

posts for cast gold inlays, 305 
Co-ordination of normal functions, 516 
Corrected radius (orthodontia), 562 
Cotton for separating, 135 
Crown, 2 
Cuspid, the lower, 17 

cervical margin, 18 






INDEX. 



749 



Cuspid, cusp, 18 

distal surface, 18 

labial surface, 17 

lingual surface, 18 

mesial surface, 18 

pulp cavity, 18 

root, 18 

the upper, 14 
Cuspid, elevation of (orthodontia), 
Cusps, 2 
Cutting of the flap, 445 



597 



Daily records, 495 
Deciduous: 

arch, 707 

cuspids, results of extraction of, 689 

expansion of arch, 605 

laterals, results of extraction of, 688 

lower central incisors, 56 

lower cuspid, 57 

first molar, 57 
lateral incisor, 57 
second molar, 58 

molars, results of extraction of, 691 

teeth, materials for filling, 379 
premature loss of, 544 
prolonged retention of, 544 
pulps and abscesses in, 359 

upper central incisor, 54 
cuspid, 55 
first molar, 55 

. lateral incisor, 54 
second molar, 56 
Decomposition of the pulp, 341 
Deductions from early symptoms of develop- 
ing malocclusion, 525 
Definition of matrix, 255 
Dental: 

cabinet, 91 

caries, 117 

engine, 180 

Pulp, 75 
Dentin, 68 

histological constituents of, 68 

treatment of sensitive, 215 
Dento-facial orthopedia, 516 
Denture, normal human, 1 
Denuded end of root, 359 
Deposits, 10 ~ 

removal of, 113 

serumal, 111 
Details as to manipulation of matrix, 216 
Development of associated anatomical 

structures, 514 
Developmental spaces (orthodontia), 507 
Deviation of the nasal septum, -,38 
Devitalization of dental pulp, 526 
Diagnosis : 

class II, 636 

orthodontia, 547 

pyorrhea, 457 
Diagram, Dr. Bonwill's, 555 

Dr. Hawley's, 556 
Discolorations of teeth, causes and treat- 
ment of, 367 
Discomfort in mastication, 380 



Disease (orthodontia), 527 
Dislocation of lower jaw, 431 
Distal movements of molars, 598 " 
Distance between holes in rubber dam, 147 
Distribution of plaster in the tray (ortho- 
dontia), 733 
Divided expansion arch, 586 
Division of teeth and cavities, 164 
Double resection of the mandible, 679 
Drilling of the socket, 445 
Drug irritants, 335 
Dynamics: 

anchorage, 567 

of the expansion arch, 569 

of traction screw, 570 

Early treatment of arrested developmental 

conditions in the arches, 606 
Efficiency of appliances (orthodontia), 525 
Electric current, 217 

furnace, 296 
Elevation of cuspid (orthodontia), 597 
Employment of matrix for gold restorations, 

261 
Enamel, 61 

chemical constituents of, 62 

rods, 63 

strength of, 68 

wall, proper bevel and polish of, 174 
Encystment of root, 360 
Engine, the dental, 180 
Environment (orthodontia), 525 
Epithelial structures, 82 
Erosion, 471 

treatment of, 479 
Erosions, 108 
Eruption of the teeth, 408 
Escape of a tooth into the larynx or pharynx, 

43 1 
Escharotics, 218 
Establishing sinus, 357 
Ether, 222 

Ethyl chlorid, 222, 386 
Etiology: 

and diagnosis of class I, 610 

and diagnosis of class II, 636 

and diagnosis of class III, 667 

orthodontia, 525 

pyorrhea alveolaris. 452 
Eugenol, 221 
Examination of teeth to discover cavities, 127 

cleanliness, 128 

concluding notes, 130 

conditions for examination, 128 

diagnosis, 127 

dryness, 128 

gingival, 127 

lines of union, 127^ 

marginal, 128 

physical exploration, 127 

proximal, 127 

records, 130, 491 

regional divisions for, 127 

at stated periods, 127 

system and method, 128 

systematic record, 127 



75o 



INDEX. 



Excessive overbite, 641 

Excision of root, 361 

Exclusion of moisture from teeth during 

operations, 145 
Expanded arch, retention of, 706 
Expansion: 

arch, spurs and hooks for, 727 
vertical alignment of, 590 

of deciduous arch, 605 

retention after anterior, 709 
Extension for prevention, 167 
External anatomy, relations of (orthodon- 
tia), 519 
Extraction, 399 

after-pains of, 434 

after-treatment of, 435 

alveolar hemorrhage from, 432 

casualties attending, 431 

complications in treatment after, 694 

deciduous, 408 

— cuspids, results of, 689 
— laterals, results of, 688 
— molars, results of, 691 

first permanent molars, results of, 692 

permanent, evil effects of, 691 

problem of (orthodontia), 687 

roots, 428 

shock during, 432 

sterilizing instruments for, 435 

under anesthetic agents, 435 

of wrong tooth, 431 
Eye-strain, 87 

Facial asymmetry, 520 

—profile, 517 

— symmetry, 517 
Faucial tonsil, hypertrophy of, 538 
Fees, 502 
Fibroblasts, 82 
Filling: 

deciduous teeth, 379 

the impression (orthodontia), 736 

large canals, 364 

materials, 225 

the matrix for inlays, 280 

root canals, 347, 363 

small canals, 365 

the use of the matrix for, 255 
Fillings, preparation of cavities for, 161 
Fissure cavities, 166 

preparation of, 182 
Floor of pulp chamber, 24 
Force and resistance (orthodontia), 567 

appliances for producing, 568 
Forcing teeth or roots into antrum, 432 
Forms of the matrix, 256 
Fracture (extraction): 

of alveolar process, 431 

of crown of tooth, 431 

of jaws, 431 
Frenum labium, abnormal, 547 

operation for, 603 
Full bimaxillary infra-occlusion, 554 
Functional influences (orthodontia), 526 
Furnaces, 294 

electric, 296 



Furnaces, gasoline, 298 

Fusing porcelain, 281 

Fusion of the roots, cemental, 



43i 



Gasoline dental furnace, 298 

Gassing, 296 

Gelatinous plaques, 121 

General anodynes or analgesics, 222 

Gingival margin, 2 

Gold, 252 

and amalgam, 252 

and cement, 252 

and platinum, 251 

and tin, 252 

inlays, construction of, 301 
Green stain, 108 
Gutta-percha, 249 

and cement, 253 

fillings, 262 

for separating, 134 
Gum lancets, 430 

Hand matrix, 259 

Harmony of facial profile, 517 

Heat, 216 

Heredity (orthodontia), 525 

Histological constituents of dentin, 68 

Histology of the human teeth, 59 

Holes in rubber dam, 146 

distance between, 147 

location of, 148 
Hooks for expansion arch, 727 
Human denture, normal, 1 

teeth, the anatomy of, 1 

— the histology of, 59 
Hygiene of the mouth, 97 

in operating room, 85 
Hypertrophy of faucial tonsil, 538 

of turbinated bones, 538 

Ideal treatment of a practical case (ortho- 
dontia), 607 
Immunity to decay, period of, 152 
Implanting teeth, 442 
Impressions (orthodontia) : 
assembling the, 735 
filling the, 736 

materials and models for, 731 
sectioning and removal of, 736 
tray, 731 
Incisor: 

lower central, 10 

— cervical margin, 12 
— deciduous, 56 
■ — distal surface, 12 
— incisive edge, 12 
— labial surface, 10 
— lingual surface, n 
— mesial surface, 12 
— pulp cavity, 13 
— root, 13 
lateral, 13 

— deciduous, 57 
mesial and distal movements of (or- 
thodontia), 598 



INDEX. 



75 1 



Incisor: 

upper central, 3 

— cervical margin, 6 

— cervical ridge, 4 

— cingulum, 4 

- — deciduous, 54 

— distal surface, 5 

— labial surface, 3 

— lingual surface, 4 

— mesial surface, 5 

— pulp canal, 6 

— pulp cavity, 6 

— pulp chamber, 6 

— root, 6 
lateral, 7 

— cervical margin, 9 

— deciduous ^4 

— distal surface, 9 

— incisive edge, 9 

— labial surface, 7 

— lingual surface, 8 

— mesial surface, 9 

— pulp cavity, 10 

— root, 9 
Incisive edge, 2 
Indications for the planting of teeth, 

443 
Inequalities of growth (orthodontia), 520 
Infant, oral hygiene of the, 97 
Inflammatory changes in alveolar tissue, 

527 
Influence of the pituitary body, 525 
Infra-occlusion, 553 

bilateral of bicuspids and molars, 

553 
class II div. I (orthodontia), 653 
full bimaxillary, 554 
-of incisors, cuspids and bicuspids, 553 

and cuspids, 620 
of molars and bicuspids, 625 
treatment of, 605 
variations of, 553 
Inharmony of the profile, 521 
Inlays, 263 

gold, construction of, 301 
indications for use of, 263 
porcelain, 277 
posts for cast gold, 305 
preparation of cavities for, 267 
the Taggart method, 302 
Irritants, drug, 335 

mechanical, 336 
Instruments: 

employed for extraction of teeth, 410 
for preparation of cavities for fillings, 

178 

— chisels, 179 

— cutting edge, 179 

— handle, 179 

— hatchets, 179 

— shank, 179 

— spoons, 179 
sterilization of, 93, 435 
Intermaxillary, anchorage (orthodontia), 

578 
retention, 705 



Internal anatomy, relations of (ortho- 
dontia), 519 

Intra-uterine influence upon arch develop- 
ment, 524 

Kerr blowpipe, 720 

Lancets, 430 

Large canals, filling of, 364 

Lateral incisors: 

deciduous lower, 57 
upper, 54 

the lower, 13 

the upper, 7 
Layer of Weil, 77 
Lever, 602 

Ligating the teeth, 150 
Ligatures, 592 

variety of, 594 
Light, 217 
Limitations of the removable appliances 

(orthodontia), 627 
Line of occlusion (orthodontia), 565 
Lingual bar and ligature, 596 

arch retainer, 710 
Lip-biting, 545 
Local anesthesia, 385 

anodynes, 219 
Location of holes in rubber dam, 148 
Lower cuspid, 17 

first bicuspid, 27 
molar, 44 

second bicuspid, 30 
molar, 49 

third molar, 52 

Magill band, 723 

accessories to, 726 
Malocclusion, 509 

classification of, 548 

local factors in, 544 

nomenclature, 512 
Management of large proximo-occlusal 

cavities in pulpless bicuspids, 212 

in pulpless molars, 212 

of an office practice, 483 
Mandible: 

double resection of, 679 

restoration of lateral half of, 684 
Mastication, discomfort in, 380 
Materials for construction of appliance, 
(orthodontia), 717 

for filling deciduous teeth, 379 
Matrix: 

definition of, 255 

details as to manipulation of, 260 

employment of, for gold restorations, 
261 

filling of, for porcelain inlay, 280 

the hand, 259 

introduction and management of, 260 

materials and forms of, 256 

mechanical, 256 

for porcelain inlay, 277 

removal of, 261 

the use of, in filling teeth, 255 



752 



INDEX. 



Mechanical: 

advantage (orthodontia), 570 

irritants, 335 

separator, 138 

advantages of, 141 
Medication (pyorrhea alveolaris), 
Menthol, 221 
Mesial and distal movements of 



467 



choice of (ortho- 
pulp, 



the 



Metals for appliances, 
dontia), 717 

Method of anesthetizing 
396 

Methods of removing the pulp, 318 

Mixing of plaster, 732 

Models (orthodontia) : 

marking and numbering of, 742 
necessity, for accurate, 730 
trimming the, 739 

Moisture, exclusion of, from the 



teeth, 



145 
Molar: 

clamp band, 719 

assembling parts of, 728 

soldering buccal tube on, 729 
deciduous, 55, 56, 57, 58 
distal movements of (orthodontia), 

598 
lower first, 44 

— buccal, 47 

— distal, 48 

— lingual, 48 

— mesial, 48 

— occlusal, 44 

— pulp cavity, 49 

— roots, 48 
second, 49 

— buccal, 50 

— distal, 50 

— lingual, 50 

— mesial, 50 

— occlusal, 49 

— pulp cavity, 52 

— roots, 50 
third, 52 

— pulp cavity, 52 

— roots, 52 

— surfaces, 52 
upper first, 31 

— buccal, 34 

— cusps, 32 

— distal, 36 

— fossae and grooves, 7,7, 

—lingual, 35 

— mesial, 35 

— occlusal, 31 

—pulp cavity, 37 

— roots, 36 
second, 38 

— buccal, 39 

— distal, 40 

— lingual, 40 

— -mesial, 40 

— occlusal, ^8 

— pulp cavity, 41 

— roots, 41 



Molar: 

third, 41 

— buccal, 42 

— distal, 43 

— lingual, 42 

— mesial, 43 

— occlusal, 42 

— pulp cavity, 43 

— roots, 43 
Mouth-breathing, 531 
Mouth, hygiene of, 97 
Mouth-wash, preparation for, 105, 106 
Muscular action, normal (orthodontia), 

526 
Mutilation of the maxillary tuberosity, 43 2 

Nasal breathing, obstructions to, 536 
Nasal septum, deviation of, 538 
Nearly exposed pulps, treatment of, 311 
Necessity, for accurate models (ortho- 
dontia), 730 

for retention (orthodontia), 701 
Neck of the tooth, 2 
Nerves of the pericementum, 8^ 
Nerves of the pulp, 78 
Nitrous oxid, 222 
Nomenclature: 

cavity, 161, 163 

of malocclusion, 572 
Normal arch development (orthodontia), 

506 
Normal human denture, 1 
Normal muscular action (orthodontia), 526 
Normal occlusion, characteristics of, 509 
Notification of patients, 499 
Novocain preparation, technique of injection 
of, 393 

Obstructions to nasal breathing, 536 
Obtundants, 460 
Occipital, anchorage, 580 

retention, 706 
Occlusal: 

relations, 507 

— of perment teeth, 508 

retention, 702 

surface, 2 

— cavities, preparation of, 207 
Occlusion: 

line of (orthodontia), 565 

normal, 509 

— characteristics of, 509 
Office practice, management of, 483 
Oil burners, 299 
Oil of cloves, 221 
Operating chair, the window in front of, 86 
Operating room, asepsis in, 89 

hygiene and arrangement of light in, 85 
Operation for abnormal frenum labium, 

603 
Operative: 

technic (orthodontia), 582 

treatment, technic of (orthodontia), 667 
Opium, 222 

Oral hygiene of the infant, 97 
Ordinary pericementitis, treatment of, 335 



INDEX. 



753 



Orthodontia, 505 
scope of, 521 
Orthopedia, dento-facial, 516 
Osteoblasts, 82 
Osteoclasts, 82 
Oxidation method (discolorations), 372 

Pathology of dental caries, 117 
Pericemental abscess, treatment of, 362 
Pericementitis, 335 
Pericementum, 79 
Period of immunity to decay, 122 
Permanent teeth, during childhood, treat- 
ment of, 381 

evil effects of extraction of, 691 
Personal treatment of patients, 489 
Phenol, 218, 221 
Physical: 

agents, 216 

explorations of teeth, 127 

relations of beauty, 517 
Pit and fissure cavities, preparation of, 182 
Pituitary body, influence of, 525 
Pivotal anchor tube, 730 
Plain bands (orthodontia), 719 
Planes, relation of inclined, 510 ^ 

of the teeth, 164 

Planting of teeth, 439 
Plaster: 

mixing of, 732 

technic, 730 
Platinum and gold, 251 
Porcelain: 

bodies, 292 

inlay, 277 

section attachment, 286 
Position of operator and patient (extrac- 
tion), 409 
Posts for cast gold inlays, 305 
Post-natal factors in arch development, 

525 
Practical case, ideal treatment of, 77 
Preparation of cavities: 

in bicuspids and molars which involve 
in the occlusal surface, 2 7 

in bicuspids and molars which do not 
involve the occlusal surface, 205 

buccal and lingual margins, 167 

bevel and polish of enamel wall, 174 

burs for, 181 

cavity nomenclature, 161, 163 

classification of cavities, 162 

definitions, 161 

dental engine, 180 

developmental grooves, 167 

divisions, of cavities, 164 
— of the teeth, 164 

extension for prevention, 167 

for fillings, 161 

fissure cavities, 166 

general conditions of outline form, 164 

for inlays, 267 

instruments for, 178 

lower incisor and cuspid cavities, 197 

management of large cavities in pulp- 
less molars, 212 
48 



Preparation of cavities: 

management of large proximo-occlusal 
cavities in pulpless bicuspids, 212 

proximal cavities in incisors and cus- 
pids which involve the incisal angle, 
198 

proximal cavities which do not involve 
the incisal angle, 190 

pulpless incisors having large proximal 
cavities, 204 

resistance form, 171 

retention form, 173 

sharpening of instruments, 182 

smooth surface cavities, 182 

steps in cavity formation, 164 
Preparation for mouth wash, 105, 106 
Precautions in planting teeth, 443 
Premature loss of deciduous teeth, 544 
Preservative forces of arch integrity (ortho- 
dontia), 511 
Prevention of thumb-sucking, 546 
Primary anchorage (orthodontia), 577 
Problem of extraction (orthodontia), 687 
Procedure for planting teeth, 444 
Profile, in harmony of, 521 
Prognosis, caries. 126 

in planting of teeth, 442 
Prolonged retention of deciduous teeth, 544 
Proper bevel and polish of enamel wall, 174 
Prophylaxis, 745 
Protrusions of class I, 629 
Proximal surface, 2 
Proximo-occlusal cavities in pulpless bicus- 

\ pids, 212 
Pulp, 75 

anesthetization and devitalization of, 

3 I 7> 3*8, 3 26 > 396 
capping the, 312 
complications incident to removal of, 

33° 
conditions necessitating removal of, 317 
methods of removing, 318 
nerves of, 78 
partially alive, 351 
removal and subsequent treatment of, 

317 
treatment of putrescent, 347, 349 

Putrescent pulp in deciduous teeth, treat- 
ment of, 259 
Pyorrhea alveolaris, 451 

diagnosis of, 457 

etiology and pathology of, 452 

medication for, 467 

obtundents for, 460 

retainers for, 460 

subsequent treatment, 469 

surgical treatment, 462 

systemic treatment, 470 

treatment of, 457 

Qualifications of appliances (orthodontia). 

582 

Reception of patients, 488 
Reciprocal anchorage, 573 
Reduction method (discolorations), 372 



754 



INDEX. 



Re-inforced anchorage (orthodontia), 573 
Relations: 

of beauty, physical, 517 
of external and internal anatomy, 519 
of inclined planes, 510 
Relative value of first permanent molar, 692 
Removal: 

of adventitious growths, 541 
of deposits 113 

of impression (orthodontia), 736 
and subsequent treatment of pulp, 317 
— anesthetization for, 318 
— complications, incident to, 338 
— conditions necessitating, 317 
— methods of, 318 
Removable appliance, use and limitations 

of, 627 
Repairing defects in impressions and 

models (orthodontia), 743 
Replanting teeth, 439 
Resection of the mandible, double, 679 
Resistance, form for prepared cavities, 171 
comparative measures of (orthodontia), 

573 

values in anchorage (orthodontia), 571 
Restoration of lateral half of mandible, 684 
Results of extraction of deciduous cuspids, 
laterals and molars, 688, 689, 691 

of first permanent molar, 692 

of second bicuspids, 694 
Retainer, the lingual arch, 710 
Retainers (pyorrhea alveolaris), 460 
Retaining wires, 719 
Retention form for prepared cavities, 1 73 
Retention (orthodontia), 701 

after anterior expansion, 709 

anterior and posterior arch, 711 

anterior part of developing arch, 707 

classified, 702 

expanded arch, 706 

of entire deciduous arch, 708 

mesio-distal changes in occlusion, 712 

necessity for, 701 

occipital, 706 

occlusal, 704 

reciprocal, 705 

scope of, 701 

simple, 704 
Rontgen rays, 566 
Root, 2 

absorbed, 360 

artificial, 449 

denuded end of, 359 

excision of, 360 

encystment of, 360 
Root canals, filling of, 363, 364, 365 
Rotation of molars (orthodontia), 600 
Rubber dam: 

the use of, 146 

adjusting. 148 

cervical clamps, 154 

clamps, 153 

distance between holes, 147 

holes, 146 

ligating the teeth, 150 

location of holes, 147 



Rubber dam: 

number of teeth isolated, 148 
rubber cups, cotton rolls, napkins, 156 
saliva ejector, bibs and accessories, 156 
size and shape of, 146 
use of absorbents, 157 

Rubber for separating, 136 

Sajou's theory, 539 

Saliva, chemical composition of, 109 

ejector, 156 
Scope of orthodontia, 521 f 

retention (orthodontia), 701 
Screw post, technique of inserting, 213 
Secondary abscess pocket, 361 

anchorage, 578 
Sectional development (orthodontia), 508 
Sectioning and removal of impression, 

(orthodontia), 736 
Sensitive dentin, treatment of, 215 
Separation of teeth, 133 

cotton for, 135 

gutta-percha for, 134 

miscellaneous conditions requiring, 142 

rubber for, 136 

tape for, 137 

wood for, 137 
Separator: 

the best, 140 

the mechanical, 138 
Serumal deposits, in 
Shading, 290 

Sharpening instruments, 182 
Shock during tooth extraction, 432 
Silver nitrate, 219 
Simple anchorage, 573 

retention, 704 
Simplified method (orthodontia), 557 
Smooth surface cavities, 187 
Socket, drilling of the (planting), 445 
Soldering the band, 725 

the buccal tube on molar clamp band, 
729 

technic, 720 
Spaces, developmental (orthodontia), 508 
Spurs, 592 

for expansion arch, 727 

pliers, 593 
Stationery, 503 

Steps in cavity formation, 164 
Sterilization of instruments, 93, 435 
Sterilizing agents, 449 
Stomatitis, 102 

Subsequent treatment (pyorrhea), 469 
Summary of anchorage principles, 581 
Superficial defects, 166 
Supernumeraries, 546 
Surfaces of teeth, 2 

buccal, 3 

labial, 2 

lingual, 3 

proximal, 2 
Surgical treatment (pyorrhea), 462 
Symmetry of the face, 516, 517 
Symptoms of developing malocclusion, 
deductions from, 523 



INDEX. 



755 



Syncope, 431 

Systemic treatment (pyorrhea), 470 

Table of average measurements, 559 
Taggart method, cast inlay, 302 

difficult cavities filled by, 304 
Tape, 137 
Teeth: 

anatomy of the human, 1 

anatomical parts of, 2 

arches of temporary, 506 

deciduous, 53 

eruption of, 408 

examination of, to discover carious 
cavities, 127 

extraction of, 399 
— deciduous, 408 
— prognosis of (orthodontia), 697 

forcing into antrum (extraction), 432 

histology of the human, 59 

implanting of, 442 

materials for filling deciduous, 379 

neck of, 2 

occlusal relations of permanent, 508 

planting of, 439 

replanting of, 439 

separation of, 133 

transplanting of, 442 

treatment of discolorations of, 367 

treatment of putrescent pulps and 
abscesses in deciduous, 359 

use of matrix in filling, 255 
Technique: 

instruction, advantages of (orthodon- 
tia), 716 

of inserting a screw post, 213 

of novocain, injection, 393 
Temporary teeth, arches of, 506 
Therapeutics for obtunding sensitive dentin, 

216 
Thrush, 104 
Thumb-sucking, 541 
Tin, 245 

Tipping up molars (orthodontia), 600 
Tooth: 

alveolar hemorrhage from extraction of, 
432 

angle of, 2 

casualties attending extraction of, 431 

escape of into larynx or pharynx, 431 

extraction of the wrong, 431 
Treatment: 

of children's teeth, 377 

of discolorations of teeth, 367 



Treatment: 

of exposed or nearly exposed pulps, 311 
of infra-occlusion, 605 

— advantages of early (orthodontia), 

609 
— complications in, after extraction 

of teeth, 694 
— early of class II, 649 
— of a practical case, ideal, 607 
— of arrested development, early 

(orthodontia), 606 
— of class I, 601 
— of class II, 636, 642 
— of class II, div. I, 642 
— of class II, div. I, sub. div., 658 
— of class II, div. II, 660 
— of class II, div. II, sub. div., 664 
— of class III, 667 
—of class IV, 683 
— of special cases, 612, 669 
— of unusually complicated cases, 

class III, 675 
— technic of operation of, 642, 667 
of permanent teeth during childhood, 

381 
of pyorrhea alveolaris, 457 
—erosion, 479 
— subsequent, 669 
— surgical, 462 
— systemic, 470 
of sensitive dentin, 215 
Trichloracetic acid, 218 
Trimming the model (orthodontia), 739 

Use and limitations of the removable 
appliance (orthodontia), 627 
of the matrix, 255 
of the rubber dam, 146 
Uses of intermaxillary anchorage (ortho- 
dontia), 579 
Utilization of time in the office, 490 

Variations of infra-occlusion, 553 

Variety of ligatures, 594 

Varnishing the impression (orthodontia), 

735 
Vertical alignment of expansion arch, 598 

Weil, the layer of, 77 
Window in front of operating chair, 86 
Wood for separating, 137 
Wrenches, 588 

Zinc chlorid, 218 















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